The thing with a BPD marriage is that you never manage to adapt. I have tried everything and I still I have received complaints.
From my experience there is mo such thing as "normal". Every marriage is unique and in normal relationships people find routines that work for both parties. A BPD partner may typically establish such a routine, then "tire" of it and project that failure onto their partner instead of leaving their relationship.
Yes the inconsistency is the hardest aspect to adapt to
Because the rules of the game are always changing. So what you have to do is set your OWN rules, play by them, and do NOT deviate from them.
To reiterate there is no normal. Just forget about it and accept the "crazy" for what it is. It sounds like you are really struggling with your husbands "needs", which a lot of us have had to deal with. The answers to your questions should come from you. What do YOU want? If you feel you are spending too much time attending to him then you have to set boundaries to keep it to level YOU are comfortable with. Some of it may come down to accepting that you may not be able to be the center of most conversations. If it really bothers you though, you should say something. Calling you a 100 times a day (as an example) while you are working is probably unreasonable for most people and you should set a boundary. A pwBPD can be really greedy and will take everything you give them. You have the power over that though and you can decide how much you want to give. They might not like it at first, but they will adjust to it. Just stick to your guns.