Liz,
I feel so bad for you that your family is so splintered right now. It's tough enough to be a caregiver without having your own support network.

Most of us patients were pretty hard on our caregivers. I can empathize with Robin - I too thought I could beat the numbers of one month of recovery for each week of treatment and it just didn't happen. I was pretty much taking care of myself about 3 months out but still too weak to return to work. I can remember trying to maintain the landscaping and only being able to prune one shrub a day (I used to do the entire yard). It's really about energy management in the early stages of recovery. Robin learned a hard lesson today. This is also about the time that depression (normally) sets in.

You have every right to your resentments and feelings. Caregiving is not for the faint of heart and, if at all possible, find a support group for yourself where you can vent and also see that you are not alone. When I was caregiving for my father there were times that I resented the impacts it was having on my life and those feelings are pretty normal (according to my therapist).