should I message her?

let me start off by saying I cannot stand this female. when my bf and I first started talking, she caused a lot of issues between us (she had dated/slept w my bf before he met me) and she has never had any respect for mine and his relationship. he deleted her off of everything and I saw where she tried to add my boyfriend back on snapchat but he didnt accept it.

I really want to message her to stop trying and just be petty because I have his heart and he talks ab marriage w me all the time🙃

(I know that's probably childish.. I just came on here to kinda vent/brag on my faithful man since I've never had a faithful guy before and its amazinggg🥰😂)