April, welcome!
I'm so glad you've found us here. There's a lot of great info, and great support.
You're not losing your mind, hon.

Well, no more than the rest of us.

I can completely relate to your "happy on the outside, miserable on the inside" thing.

A friend once told me that I'm the happiest depressed person she's ever seen.
Have you ever considered seeing a therapist/counsellor/etc? It's wonderful talking to someone who has no connection to your "real life". That's one of the reasons I love coming here. No one here "knows me", but they "know me REALLY well!" If you know what I mean.
In any case, we're here for you anytime.