Hey there, I'm not on Tamoxifen yet but had trouble all through taxol with sleeping. I think the stress of the chemo, anxiety, lack of energy and hot flushes combined to stop me sleeping. I did take Ativan for a while then sleeping pills to get past the worst. I was getting in a cycle of grumpy and snappy due to being tired. Then eating etc etc like you mentioned...a bad cycle.
I stopped taking all meds after taxol a month ago and switched to Swisse sleep, recommended by a friend. I also now exercise about 1 hr 5 days a week. So far so good...sleeping better, not great but improving.
I also find music while going off to sleep distracts me from my thoughts and lets my mind relax.
I'm not looking forward to tamoxifen, sounds like the hot flushes will be here to stay.
Take care
Louie