My 2 cents: The changes I make in myself - my relationship behavior and attitudes - are meant to become permanent, for my own sake. They are independent of H and the M - they are all about me improving myself to my own benefit and the benefit of whoever I have a relationship with. It's like losing weight - I may initially be motivated by looking more attractive to my spouse, but the purpose is really to be healthier and have more energy for myself.
My activities and interests may change, with season, ability, energy levels, etc. Although trying something new every so often keeps you interested (and interesting) and 'awake', I think.
As for spending the 48 hours together, I would think of a way you can suggest also doing something separately during that time (maybe take one kid and do something the other doesn't care for), and that you focus a lot on the kids and only intermittently on her. You can give her little flashes of attention, but mainly respect her wish for space (which I assume she has expressed a need for?).
M 16 yrs, WH62, P54 3 adult blended kids EA 11/13, BD1 6/14 PA fall 14, BD2 2/15 Piecing 2015, BD3 12/15 Separated 4/16 WH moved OW in 5/16 Divorced 6/15/17
