((((((((((((((mixedupemotions)))))))))))))))
Wow, you mentioned a lot of things in your post that are certainly worth talking to a therapist about. And you deserve to do that....to work through your OWN issues, and let yourSELF heal.
You don't have to tell him about anything you don't want to at your first appointment. Or, you can tell him everything you said in your post. It's up to YOU. Don't worry about whether your therapist is looking forward to "an easy day". He is doing this job because he wants to help people.
I used to worry because I came into therapy basically saying "I'm kind of stressed out" and ended up sharing ALL of these HUGE issues with him over the course of our therapy. It's very intense, and probably not what he expected. I told him once I was worried because my issues feel so big and he's probably actually used to people who are really, truly just "kind of stressed out"...and he told me he would get bored if that's all he dealt with all day. I know it's challenging to work with me, but I think he likes it. I bet your T will like working with you too.

