So confused

So this guy im talking to ..we have a history so i dont want to get into the long story but i care about him and hes going through a lot right now he has health problems and the doctors are saying he has a 50/50 chance of living 5 more years. So im worried about him but i dont want to push him to talk to me about things and when hes going through a lot he likes to keep to himself..and he says he doesnt know what to do right now that he likes spending time with me and i make him happy but then other days i feel like he ignores me and i bother him so im trying to find the line where he knows im here for him but not to much to where i annoy him but then also i wnt to make sure hes ok and not push me away from him