Struggling with Mental Burnout and Motherhood

I am considered disabled due to mental health reasons, and I think I'm being a bit hard on myself???... I know I'm capable of functioning, I have before; but when I'm experiencing mental burn out I'm so exhausted all the time, mentally, emotionally, and physically. I barely have enough energy to keep up with things. I get distracted so easily and I lose track of time... I am also a mother of 2 children; one is not in my care, I lost her during an abusive relationship, the other I have with me after leaving my abuser and she is doing well. her health used to be so poor, and now she is getting the medical attention she needs. I'm her only advocate and I've gotten things done for her... sometimes I feel like I'm not a good mom, or I'm not capable of being a good mom in the future because of these burn outs and just the fact that I'm considered disabled... is this just a single mom thing? it's also winter, I feel so bad because there is not much to do in the winter, it's to cold. but I have loads of plans for the summer. idk, midnight thoughts, and sometimes they get to me... thanks for reading