I agree, that's a tough situation. It sounds like you have been flexible and patient with your T and with her need to take a break for family reasons, which is kind of you.

At the same time, you are a paying client who has been transparent that you want to do long term depth work twice a week. IMO when a therapist offers to provide long term regular therapy to a client they should be able to offer regularly available weekly sessions without interruption (other than emergencies or that sort of thing). I wonder if she'll be able to provide that kind of consistency and dependability to clients going forward? It will be hard if she is planning another pregnancy and then raising very young kids. But maybe she can do it? Anyway, I think your pain and concern is justified.