<human>: I had this girl I was best friends with for years, from the time I was 14 until 22, when I cut her off and went NC... until the other day. I could elaborate on this girl and why I chose to cut her off, but I think I can trust r/relationships to believe me when I say it was for the best. Very brief summary, she tried to ruin all my college friendships (basically did, honestly, they were never the same after) by spreading rumors about me, inviting them to things and "forgetting" to mention they were all hanging out together, suggesting I was "Crazy" (I was suffering from depression for two years prior) and also doing things like constantly belittling my (at the time) recent weight gain. I am not big on just cutting people out of my life but at the time I really had no idea how to deal with her, because the meaner she got the more clingy she would also become. Was strange. 

Life circumstances (a wedding) mean that I will have to see her/be at relatively intimate parties with her for the next year, so I wrote her a very long and I thought polite yet heartfelt letter where I said I'm sorry if I hurt her by cutting her off but at the time it was what was best for me, and I hope she knows I harbor her no ill will and I hope she accepted my optimistic gesture that we could be cordial at the upcoming events. 

She sits online all day (no joke) so I know she's seen the letter, but no response. Should I bother following up? Of course one of my old college friends who I never talk to anymore immediately gchatted me after Id' sent it, so I'm positive she immediately mentioned the letter to her and was hoping I would start talking about it to said mutual friend, but I didn't want to (and it was SO obvious that was the reason the girl IMed me... wasn't even subtle) but I wondered if I should bother asking the mutual friend if what she thought of it.

Give me a shortened version of the text
<bot>: Had an awful falling out with a girl who treated me like shit, but was years ago and will have to see her at some events, wrote her letter asking to be cordial, no response.