It's good to be upfront about these things. Holding stuff back potentially keeps you from getting adequate treatment and can actually result in the wrong treatment. It's good that you're going to get a referral for a therapist. IDK how your medical system works, so please forgive this question if it's stupid: When you say going to a therapist, do you mean one who will prescribe meds? It's important to have a psych doc do your meds so you get the treatment you need. I think of it kinda like asking a neurosurgeon to perform cardiac surgery. Yeah, that was covered in med school, but the heart and brain are two different systems. Similarly, a GP had psych coursework, but it's not something s/he is proficient in.
I hope your appointment goes well. Hopefully it'll be a relief to get it all out.

(Sorry if this is rambling.)