Hi there,
Your description made me laugh. I like to think of myself as a self-sacrificing, dysfunctional, social fawner/freezer
in recovery 
and it's kind of nice to be able to say that without shame.
I'm a lot better with my social anxiety now, and I can't really say why beyond something happened to me and I stood up to abuse and then stood up the the shitstorm of vicitm-blaming that ensued. It was a kind of social death of ostracism (my worst fear) in one way, but a new life (I hope) in another. Social anxiety sneaks back up on me often, but there are times when I genuinely don't fear rejection or disapproval or what people are thinking, and it's a real freedom.
I was looking up my brother's number for his birthday and realised that most of the numbers in my phonebook I need to delete after finally reaching the point of full-up, can't take any more *. I realised the consequences of radical action could not be worse than the consequences of living as I had been - endless disrespect and abuse. I walked away from from all toxic relationships, though to be honest, in some cases the ostracism from confronting an abuser took care of some of them, but I still walked away from the rest when I was at my lowest ebb. Pretty gutsy huh?
And then I thought something else - the numbers were of the most disordered and abusive members of the groups I associated with. I thought why were the most toxic people of all the people who were around me, reclusive as i have been, the ones I associated with most?
Answer, (in case you haven't guessed) - critically low self esteem, almost non-exisitent boundaries, desperation to belong and be liked, loneliness, social isolation...you get the picture. Trying sooooooo hard and feeling a kind of pathetic gratitude to anyone willing to be my friend. I'm not blaming myself here. Most of the time I'm just glad to be part way out of the storm.
And guess what? I'm becoming closer to some good people who were distant friends. By trying less hard, and being more open, trusting myself more.
Hang in there, social anxiety can get better. (And not necessarily via a blitzkrieg either)