Maid of honour and best man drama!

Okay so me and my oh chose our MOH and BestMan a while back, they didn't know each other at all untill my MOH started saying she thought the BM was fit from a facebook profile pic, she was newly single, she is that friend who has a lot of man drama! there isnt one ex boyfriend that I can think of where things have ended on good terms, anyway she wanted to message him I said she could if she wanted but i expressed my concerns that If they dated and fell out It would be very uncomfortable for me and my OH on the wedding day to have our BM and MOH as ex's who didnt get along. So they message, end up texting me and my OH to say they are meeting and they wanted to be honest with us, fast forward 5 weeks later she is crying over him because he wanted a break over a disagreement they had. So i say to her look there's drama already, we really don't want you two too not like each other for our wedding- you only met because of our wedding anyway. She says i am ruining her happiness, the Best Man goes to hers to collect a few things he left there baring in mind they was only meeting for 5 weeks and she knows the bride her best friend is really worried out this and has asked for them to just stay amicable and not complicate things any further. They hook up instead of him getting his stuff he stays the night which he says was all instigated by her refusing to get off his lap and making him come in to get his stuff ect. So i get cross, say lots of harsh words because i feel let down by my MOH and best friend. She says she is an adult and can see who she likes, we currently are not talking. I just really don't want to have 2 people that are exs and dislike eachother after a breakup either side of me and the groom on the big day, the fact she still hooked up him with again after i had made it really clear and things where not going well has made me really mad. She wont appoligise and says i should appoligise I'm having a really small wedding with only 40 guests, and they did not know eachother before being Best man and maid of honour. Do I have the right to be cross or am i over exaggerating? How would other brides feel about this. Thank you in advance x