Ugh! I would be totally freaked out if I found a page for my bmom and it looked like that.
I agree w/ Suzie about not fessing up just yet. I think you should do the following:
1. Unfriend your husband from C's account
2. Clean up your myspace page. Do not have a song popping up about "suck my d*ck!!!
3. Tone down the "People I'd like to meet" section. (you don't want to sound desperate or obsessed w/ her)
4. Unfriend your husband from your page
5. Contact her yourself
6. DO NOT bring up anything having to do with posing as your husband.
I think what you did is better left unsaid.