Struggling with Basic Things and Finding Motivation

I'm having trouble with "basic" things (eating, sleeping, etc.) and I was wondering how to develop a routine and stay motivated about life? I feel like I don't really have much to look forward to. I can't work outside the house because I'm a caregiver for someone who needs constant supervision but sometimes I think it's better that way since I can't even stay caught up with my freelance work anymore. I feel like I don't do much all day except strategize how I'm going to cope, which leads to overthinking. I'm always just distracting myself (movies, TV) and I can't imagine much of a future for myself. Sometimes I've thought about setting a schedule for myself, but my sleep has been so unstable/unpredictable. I just try to sleep when I can and some nights I just don't sleep or sleep only a few hours. I feel like no one has messed up their life like I have (I know that's a huge exaggeration but that's just what my brain will be telling me during dark moments). I don't really find joy in little things anymore. I feel overwhelmed by everything that's happened in my life and I'm not sure where to start or if it's even worthwhile to try and get myself together.