Have namechanged, because I feel like a complete cow for feeling the way I do and I am a coward.
My very good friend met a man three weeks ago and got engaged after a fortnight. She has now set the date for the wedding.
Her family have been pretty silent on the matter, but his have been popping up all over facebook congratulating the happy couple and they seem thrilled about the whole thing. They also threw a party for them the day after the engagement, which hardly any of her family attended.
I have been introduced to this man, and didn't like him (I made sure I hid it though). Mind you, I will be upfront and admit that I had already pre-judged him on the only two things I knew about him - the quick engagement and also the fact that he had suggested that they have a joint facebook account instead of seperate ones. 
She is excited about planning the wedding and wants me to be excited too and to join in with the wedding planning.
I have gently suggested that this is very quick and asked if she is sure about it all, and she got very defensive so I brushed it off and congratulated her. I feel like I can't be happy for her, because I don't approve of it.
Just to give some background and so as not to dripfeed, she has a long history of severe depression and so I worry that she is vulnerable.
I expect to be told that I am a bitch who should be happy for my friend as she would be for me, and to keep my nose out of her business, but I can't help the way I feel.
AIBU?