
to you.
You know, there is a prevailing sense in our culture that it is wrong to 1) have feelings, 2) take care of ourselves, or 3) not be scheduled to do something at every given moment. I've taken to a certain exercise whenever I'm feeling this kind of pressure. I basically repeat one of the following to myself.
1) I am the only one who gets to decide what to do with my time. It is my decision, no matter what other people think.
2) It is ok to be tired/angry/sad/etc. Those feelings are part of being human, and I am allowed to feel them.
3) I don't need to justify my decisions to anyone.
It is a VERY hard cycle to break, trust me, I know. But no one requires an explanation. "Oh, thank you so much for the invitation, but I'm afraid I won't be able to make it" will suffice. And if they ask why, "I just can't make it, so terribly sorry, hopefully we can get together soon!" Or, with your husband, "I just can't do it this week. Sorry!" and if HE presses or asks why, "Honey, I really can't manage it this week due to XXXXX, but maybe you can invite so-and-so to go with you".
This will be weird for people, because if you are like most of us, they are used to you sucking it up and going wherever or doing whatever they want. But eventually they get used to it.