I want your opinion on my situation that im in. am i in for more heartache?

my story is long and drawn out. if you read it completely you deserve 10 pts just for that. i been caught in a love triangle w/ my ex gf and her babys daddy. i have been involved w/ her for a yr and a half now. we broke up last week, quite possibly once and for all. ultimately she chose money and stability over love(sadly for me) and well while its intolerably painful for me(and supposedly her) i cant live w/ her choice and from what i hear from her sister she cant either. her sister is on my side and thinks she should be w/ me, just bec i treat her so well and we get along well compared to her kids father. and while i have been trying to avoid talking to her as much as possible, her sister texted me yesterday and told me theres a letter that i should read that my ex gf has been working on. i dont want to drag the pain along any longer, so im in a situation where i dont even know if i wanna read what she has to say, i also dont know what purpose the letter would serve at this point, but u cant control your feelings and i cant help but wonder. im not asking you to be a tarrot reader and tell me whats in the letter, just your opinion on my situation overall, if you have been in the same situation like me and last but not least how you would handle this situation yourself. thanks!