Worried for OCD/AVPD partner after breakup

My OCD/AVPD boyfriend of 7 years split up with me exactly 1 month ago, It's been gut wrenching.

Over the last 2 years he had fallen into a bad mental health space with his OCD/AVPD, I'd been trying my best to support him but he has slowly disappeared from me and at the same time I've had to deal with his abusive toxic parents trying to split us up for the past 4 years.

His parents have no awareness of the day to day reality of his Pure-O OCD / AVPD, and turned even our relationship (which was I feel his safest space) into a pressure for him.
Over the last 3 months he finally decided to go back to his psychologist which I was initially really happy about, because I felt like finally he had another person to support him and it wasn't just me propping him up anymore. It had taken 2 years of encouragment from myself, family and friends to get him to go back.

I caught an awful virus in January, and had to go into hospital for a week and I think it finally pushed him over the edge with his intrusive thoughts / obsessions, we had an awful argument about his abusive parents a few days later while I was recovering, which made him angry enough to start smashing things.

I wasn't in the best frame of mind, his parents had forced him to take a holiday to another state and I was afraid because I needed him to help me out and stay an extra day or two. For the past few years I've been so careful to be strong, not show him how much taking care of him was a load on me, not showing how much it hurt dealing with his parents manipulation and toxic behaviour, or how they would get at me using him as a proxy when I finally decided to start ignoring them.

For the first time in a long time I let myself go and screamed at him to take his things and go or I would call the police. I have ptsd and I was so scared when he smashed the pottery and yelled at me that "I didn't trust him", I didn't want him to leave though I wanted him to go somewhere and cool off. Instead he went to his parents and they convinced him to leave me, I got a text 2 hours later that they where bringing the trailer up to get his things. I wasn't supposed to be walking but instead I was vaccuming up the shards of pottery because I'd called my parents to come up and help find him. I managed to ask him on the phone to calm down and go on his holiday, forget about this and just take 3 weeks off from everything.

Since then he's not been the person I used to know.

I think he's seriously unwell and has completely shut me out because I'm the only one who can see how unstable he is. His behavior of recent times has reminded me of my younger sister who has schizophrenia, she's been through a few episodes of psychosis before, it feels eerily similar.

He's had face to face contact with me twice, both times we talked until the morning and it was really difficult because one minute he said that he was unwell, couldn't get better being in relationship or in this house with me (I assumed it was obsession/compulsion related) wanted to be well and get better, get help, then come back to the relationship.
We hugged a few times, he said he'd missed hugging, I was so happy, but then the next minute he wanted nothing to do with me, and that he couldn't even come see me once a week to let me know how he was doing, he didn't want to see me at all. It made no sense, he couldn't give reasons. He didn't sound like himself at those points, it was like talking to 2 different people, one very emotional / crying, like the old him I used to know, and then the other very cold and short sentences.

After those 2 evenings of talking till 5 am, came the day he collected his stuff which I very carefully packed up for him, because I've realized there's nothing I can do and I just want to support him because I still very much love him, I decided to write a letter to his psychologist to explain what had happened from my position and how worrying it is to know that he's running around with people that have no idea he could be in a mania.
His psychologist never replied or confirmed that he'd got my email, and I figured well that's okay I guess, maybe he didn't get it.

Then this week I got a letter in mail box from my ex saying why he's breaking up with me.
It was so hard to read because all I could see where things his mother had obviously told him to write, his best friend had a divorce 6 months ago and cut his poor wife out in exactly the same way and I feel like my partner is just emulating the people he's spending the most time with right now. It's not like him at all to just cut someone out, he used to dependable and reliable, honest, genuine, that's what I loved about him. I feel like if the things he'd listed as issues where genuine issues he would have at least tried to work on them with me, what's even stranger is that he brought these issues up with me the last 2 times we talked and I told him that I was completely willing to get help and work through them, and that I'd actually changed my mind about one of them while he was on holiday.

What shocked me though most was in this letter he said his psychologist had received my email, and that his psychologist had actually let my partner read it.
I'd sent this letter to his psych in complete confidence, I wanted him to know that my partner is very unwell, might need medication to help come back down, and that he might be totally telling his psychologist "everything" in his appointments.
My partner said his psych had explained that he was "Ethically Obliged" to show him the email. Would it be professional of a psychologist to actually do something like that?
I feel utterly betrayed, not that it matters because these things are all thing I've tried to discuss with my partner and the bulk of the letter was that I was very worried for his welfare now that he's living with his parents who don't have a good grasp of his mental health issues.

I'm so broken now, the day I got the letter I tried calling him but he had already blocked my phone number, I tried calling him via facebook and he just refused to pick up. I left a few of those 1 minute voice messages saying that I'd felt suicidal the last 3 days and I can't believe that he can't see what he's walking away from, that he's losing his best friend. I haven't made any contact since because I'm sure he's just going to make out that I'm crazy to everyone around him now, It's all just too much for me. We spent so much time together before this happened, 7 years through thick and thin supporting each other through everything. I thought we were going to spend the rest of our lives together, and he knows I'd support him through anything I don't care how mentally unwell he is I would never leave him even if he was in a psychosis or having really bad obssessions around sex/violence or whatever. He never left his key to our house which confuses me.

I'm so broken I'm not sure what to do anymore, I haven't made contact with him since he sent the breakup letter and I left those voice messages on his facebook. I feel like for him that's that and he's just going to surround himself with people who don't know how truely unwell he is and live this weird lie. I don't know how long that can work until he falls apart, I did a lot of things to help support him with different aspects of his day to day life that people like his friends and family don't know about.

My own family and friends are all just telling me to get over it, but it all feels wrong just forgetting about it. I spent 7 years with this person, I thought I was going to watch him get old and have children and a life with him, I try to stop myself thinking about it but it's so hard. Currently he is living with his parents literally live 5 blocks away from my house so I'm scared to go out in case I see them, I've been shut out and I feel like a mushroom in the dark. I can't figure out what I did wrong or why he would shut me out so hard, what's worse is the things he wrote about as a reason for the split are things we could definitely have fixed if he'd brought them to my attention in more than a passing way, he expected me to just fix things a lot of the time on my own which felt weird, I want to fix things together. I don't know what to do anymore, the worst thing is I just wish he was here despite everything that's happened. I miss talking to him everday, and saying goodnight and feeling safe because he's here. My home isn't a home anymore.
I'm sorry this post is so so long.