I am so sorry to hear what you are going through. I also suffered a breakup with my fiance where she quickly went to a guy we had both known for years whom she never once had anything nice to say about while we were together. In fact, she had said quite a lot of not so nice things about him and now he is my replacement.

I am shocked at how instagram is flaunting their relationship in your face against your will. I am on no social media (except forums like this) so I dont have to deal with any of those things. I dont know anything about how intagram works but is there no way to block that from happening? Having to see that stuff can not  be healthy.

Take care.