So me and my SO been together 10 years well at the beginning of the relationship there was this girl who tried to get with him even doe she knew I was already dating him. So I never talk to her or even say hi. Well 8 years later we had our first baby and we seen her and my SO and my sister in law told me to give her an invitation  to my baby shower well I didn't think of the pass cuz it was long time ago something like bury the hatchet. She never showed and on the back of my mind I still didn't like her so I just ignore it and now that we see her more I still don't say hi to her or her to me. By the way she's best friends with my sister in law. I never told my sister in law I dislike her but there so manau occasion where there all togheter and we don't talk. Well now she called my SO I'm like why da fuck would she called and she called to ask if he can fix her car when she knows damn well he don't know about cars so it just made me so furious and I told my SO I don't want her or him talking to eachtoebr I just exploded and I told him everything because I never told him from the past. And he's like well you know how she is! And I told him I know so delete her in snapchat idk how they became friends on snapchat! She is married and with two kids but it bothers me I'm I wrong????