Hiya @TAB ... 🖐
Welcome to the forums @Lostkiwi.
That's a tough place to be, and the answer isn't simple, but it is do-able .... often self-esteem has worn down in small stages, and we add a lack of self-care to it by giving up on ourselves a bit.
So .... one of the first steps to regaining a sense of self-worth is by looking after ourselves ..... doing one small thing a day that leads in a better direction, and many here have found that one of those simple things can be turning around and making your bed (in some form or another) when you get out of it in the morning. It's saying to yourself that you are worth a made bed. It also smartens up the room in the process, no matter what the rest of it looks like, and it's something nice to come back to at the end of the day. Making the bed also gives you space to lay things out on it like a work-bench of sorts, to help with sorting, or organising what you are going to wear, or whatever.
I call them "baby steps" .... taking small steps as and when you can to support your well-being in your physical body, even though that can take a while to reach through the fatigue, melancholy, sense of flatness or wanting to hide yourself away.
Please keep posting here. There are others who feel the same who appreciate the company of finding someone else on the road with them .....
Have you taken a look at Social Spaces on the forum ? You might find some common interest areas to share in. There is also the Good Morning thread to have a bit of a check-in meet-and-greet ....