What, I can empathize, as your explanation mirrored my weekend. My agf was literally showering me with compliments on Friday, and then all at once started accusing me of witholding affection, not validating her sufficiently through compliments, and not fulfilling her sexually on Saturday. It can be a very chaotic and confusing cycle, but I have noticed that the downside usually comes on the heels of an alcohol episode, or most recently when I started taking care of myself (exercising regularly with or without her, eating healthy whether she did or not, etc.) and not her or her illness.
Not allowing him at home is, in a sense, yanking the safety net out from under him, and it seems as though the blame game is a gambit to try to make you feel responsible. If you're feeling guilty, you'll have a harder time sticking to your guns, and he'll have his safety net back.
And don't feel too bad... I need to make it a point to re-read these very same words at times. Progress.