My (40 F) husband’s(42 M) girlfriend (23 F) threw my daughter’s birthday cake in my face

My husband's girlfriend: Sasha

My husband's girlfriend's daughter: Sam

My oldest daughter: Vic

My husband and I have been married for 17 years, he was unfaithful to me several times but I forgave him because I really loved him. But then he went with one of his lovers. She is 23 and has a daughter (Sam).

We have not started the divorce process so we split custody of our children 50/50. He moved to a house near where I online with our children. Since we are close, they go whenever they want. Vic had already told me several times that Sasha treats her badly, makes sarcastic comments, among other things. I went to complain to Sasha and she played the victim but left our children alone.

Also, every time my husband buys something for our kids, Sasha makes him buy Sam the same thing or a higher value, but I really don't care about that as long as My husband fulfills his obligations.

A week ago it was Vic's birthday, she wanted a trip instead of a party. My husband bought the tickets (for our 3 children and me). We had a small meeting and there my husband gave the tickets to our daughter, Sasha went crazy, she started yelling at him that she had asked him for money to buy things for Sam and that he told her that he didn't have money, but that he does have to buy some tickets and pay for the entire trip. He simply said that Sam wasn't his responsibility.

She started yelling that she and Sam are now her family and that they should be given priority instead of us.

Sasha grabbed the cake and threw it in my face, so I had no choice but to throw her on the floor and hit her. I also told her to stop messing with my children, and they had to separate us.

My husband is still with Sasha but I don't really care and I'm writing this while on vacation with my kids lol.

Also, I have tried to start divorce proceedings but my husband keeps putting it off, saying he doesn't have time. Should I leave the topic of divorce aside? I think that marriage, like divorce, is a simple legal paper and he is really already fulfilling his co-parenting part.