Can't believe this is still going. I had a whole thing typed out but honestly I don't want to share my own experiences so all I'll say is, as someone who has gone through something similar, get some space and get some support. I don't know what your deal is with your mom, but if it's ego stopping you, you need to let that go right now. You don't need to live under the same roof to take care of the kids during the day. If you really want to stick to looking after them for now, go look at doing some online courses as well, because from the sounds of things you're going to REALLY struggle when you actually try to get your own income. Or some part time work/university. Just do SOMETHING, because right now you're acting like a child getting pampered. I was sympathetic at first, but the more follow-ups I read, the more I feel like you're not taking this seriously. Yes, it feels comfortable for now, but you really need to get some independence and agency. As for what you actually contribute? I'm not convinced, because you've already admitted you don't have much experience and you don't cook, and that you've struggled with depression. Yeah that sucks, I get it, I've had schizophrenia and depression since I was a kid but didn't try therapy until about a year and a half ago. And even just sticking with therapy is difficult, I've been on and off it constantly.
I'm rambling, all I mean is that you can still have your own life and still be in your kids' (and ex if you want to keep it friendly) lives without physically being there constantly.