Lucky you - you get hormones!!! I've also had breast cancer so no hormones for me. Yes, Sleep is never easy! I often found myself lying awake. I also have infusions of Rituxen by itself for my RA. I suggest keeping some Benadryl handy - non habit forming and quite effective at making you sleepy. For emergencies I have some Xanex. I think the Rituxen contributes to some wild dreams which can wake me up? Several of my friends take a sleeping aid.
My daughter has suggested yoga and meditation - she may be on to something :-)
Good luck and sweet dreams.