I have been wondering how you were doing, and am so sorry. Letting a beloved bunny go is a terrible decision to have to make, but you thought of what was best for Monty. I have doubts about decisions made concerning Riley's care...and there are still days where that time comes back to me after all these years. Hindsight is 20/20..or pretty close to it.
Your doubts about staying with Monty's vet are something you need to take a bit of time to think about...listen to your gut. It sounds as if you feel he shouldn't have prescribed steroids for Monty.
Good thing you have Lily..she can be a comfort to you.