I find it so hard, not in terms of keeping healthy because for me eating well and exercise is just luckily habit that I've formed since childhood, but that's just luck that it's ingrained. On the other hand I find it really hard to self-soothe and self-nurture when I'm feeling any intense emotions or depression or anxiety. I go for harmful behaviours rather than self care.
My main problem is not feeling like it'll "connect" with me...like it will just be pointless, because I don't have an anchor inside me or something. Not sure if this resonates with anyone but we've been over it in therapy. In the past my T has told me to just do one small thing a day. If I've been going through a difficult time she tells me do one small thing every day for a week, such as cooking your favourite meal, reading a poem, buying a chocolate, sitting outside, and being aware that you're doing this as a special self-care thing. She said don't worry if it doesn't feel like you're connecting with it, it will build up anyway.
Hope that helps a little.