If I'm right, I can promise you that this is a completely normal feeling. I was terrified after all my treatment was finished! It probably took me about a year to truly move on. I was in total denial during treatment the entire time!
I'm also on hormone therapy. I'm a 7 year ER+ survivor, Stage III. As time goes on, this truly does get easier. It definitely takes time. I think it only makes sense after you've been through any serious illness, or trauma for that matter, to get your life back. It's a new "normal".
You can do it.