I hear you @frog about all of that. The need to be productive is strong in many of us I think. Been programmed by society to feel that way. I too still have issues with the concept of 'just for me', but I have learned how terribly important it is, so do try to do something for me. Sometimes I combine the two, just for me and productive, that is mostly with my crochet - I don't have much of a use for purely decorative items since massively downsizing and trying to keep from regathering. I make one-of garments for myself, as my process of 'just for me'.
What I enjoy most is almost always a hand craft skill, at the moment it is tatting the edge on a couple of hankies for myself (ongoing saga in Craft Corner if you'd like to visit).
I even have difficulty growing flowers just for their flowers and not being useful in cooking. Yeah, how sad is that! I tell myself it is about the work/ gain ratio, but I think I'm going to plant a pot just for flowers in the coming weeks. My garden is container only and a very small space now, but I have herbs and a Bay tree and various other things that are useful. The gardening is a real joy to me though. There are some flowering shrubs and a few bulbs in the ground but they belong to the body corporate, I pick the flowers though. 
During the marital years there was lots of troubles, as there is with so many of us, and we got some advice from someone I'd previously trusted (a religious body but where marriage was allowed). Ex had problems with me spendiing time crocheting at night instead of watching tv doing nothing. The Rev Mother sided with him as I was wasting finances on putting pretty edges on serviceable items like face washers. What they didnt' take into account was the number of gifts I made and the savings I made by doing those crafted items. I enjoyed the look on her face the day I handed the sister who had become a new mother the baby bath set with crocheted edges and embroidered towel and so on. Her judgement was so easy to make without letting me tell the full story. I have a name for those people and it's not a nice one!
I read every day, so maybe reading is my favourite - the only times I don't read is when I am really seriously way beyond low. I also sew, but that is often from necessity as I make my own clothes. But I enjoy the designing and then the choosing of fabric and the making it up - except when I mess up, but then the joy comes from being able to cleverly patch up the mistake so it looks like it was meant to be there!
Yeah, I have been having trouble for the past year getting back into my writing myself - I haven't managed to get to doing that 'just write thing' although I write so much of other stuff, just not my stories. go you for getting some work published, very nice. It is a 'thing' worrying about being exposed when you've written about yourself, so I can empathise there too.
Perhaps, just an idea, as it's what I do to combat that 'I have to' feeling, can you rearrange your set up so there is less to do, make others a bit responsible for some of their 'stuff' ( I think you have kids at home? or maybe I"m misremembering that).
One of the first psychs who was useful to me told me the younger kids were old enough to make their beds and get their own cereal breakfasts. Yep, I was the oldfashioned mother who did it all. they were 7 and 9.
So to make it easy, I changed their blankets and sheets for doonas and a bottom sheet and they had to just keep it straight. Set the stove timer for certain jobs and off we went. They hated that psych needless to say, but they are all very capable adults now, they had to be.
Probably too much information - sorry - I'm up way early because can't sleep, very bad night. Hope you find a way to help you get through each day @frog 