I need your advice, please!

My husband was married from 1980-1988 to his first wife.  My husband and I met in 1997 and got married in 1999 and he passed away in 2009 ...so I never met her.  She found out that he died last week and wrote me letters full of questions...such as how he did it and if I was the one who found him. I just told her that I was having a hard time and really didn't think I could talk about it right now.  She called my mother in law and they had a long talk.  My husband had told me she left him for another guy but she told his mom it was something else that made it all his fault. Now she is friends with all my inlaws on Facebook.  She asked to be my friend but I just couldn't.  It's not that I have anything really against her.  I just don't know her and don't really want to share all the personal stuff between Billy and I.  She told me if I ever felt like sharing or had questions to let her know.  She said she was broken hearted and he was her best friend and she couldn't imagine not talking to him again.  When would she have talked to him?  She left him and they haven't had contact since she left in 1988.  I am not a mean spirited person but this is really hurting me and I have to get it out.  My mother in law even signed her facebook message to his ex as "Mom".  Now she (his ex) posted that she was glad there was a FB page for Billy.  It's the one he had when he was alive but she saw that his mom became his friend recently so she thinks its new.  I got on his account and invited his mom because she wanted to see his page.  So she (his ex) sent a request to be friends with him too.  I don't want to accept the friendship because that is where I go to write him letters.  The only people left on his account besides me, is his mom, sister, and brother.  Why am I feeling all these emotions???  I don't know what to do. I am really miserable seeing her name everytime I go to one of his families FB walls.  I am the kind of person who sort of stands back so I haven't written on their walls much.  I don't really want her to see what I say to them since I didn't accept her friendship request.  Has anyone else been in this situation?  I know she had a place in his life but it was so long ago....and she's married now with two kids.  Am I mean or just crazy?  :S   I would really appreciate any advice you can give because this is really causing my heart to hurt...Maybe I'm jealous of her relationship with them because they're all I have left of him?  I know I'm rambling...but I just don't know what to do. I know I can't tell his family what to do so I just have to accept that they are going to be friends now.  Another thing that bothers me is that some people have acted as if I should be over the pain by now. It's been a year and a half.  It breaks my heart as if it were yesterday...but I rarely get emotional around anyone.  I just cry when I'm alone sometimes...but my heart aches to have him back.  I think of him every morning and every night...It was such a shock to come home that day and find what he had done...I honestly think it's changed me for life...arrrghhh...help, please!!!