Husband with PND

Hi! I have a 5 month old baby boy and I've just realised that my husband is suffering from PND. He's recently started a new high pressure job that has him working longer hours and a bit of travel. I feel like this job has triggered a bit of a breakdown. He's been much more distant lately and upon questioning him he has stated that he doesn't feel any connection to his son and no passion for anything in life including me. I'm devestated honestly and had no idea things were this bad. He says he loves his son and me but feels emotionally numb. He's had a rough past which i think has perpetuated this. His father was quite abusive and committed suicide when my husband was four. He says this isn't an issue but I beg to differ. We also went through two years of male factor infertility and eventually conceived through IVF. Naturally he has supported me through all of that and I couldn't have asked for a better husband and support. But I feel he's been strong for me a so long he's neglected his own mental health. He's been very involved with his son until this point however recently he just has no interest. He's agreed to see a psych and that's a positive step. He's booked in for two weeks time. I'm really struggling to help pull him out of this and am devestated for both him and my son. He said yesterday that he thinks my son and I would be better off if he left which is just not true. Any words of comfort or advice? Thank you