You sound like an almost mirror image of myself. The best word I ever learned to use in these situations is "No". "No I can't do that today.", 'I'm sorry, but today I just can't help you with this", etc. It's not that I always turn people down (I don't think that is possible for me), but I had to learn that on my hard days, especially those days, it was okay to take care of myself first! It felt selfish and strange to start with. The way I made myself okay with it, though, was with the reasoning that "If I don't take care of myself hoe can I continue to help others?"

Don't know if that helps (or even makes sense ), but I hope you will find someone to help you learn how to take that load off your shoulders!

AA