What to do!!

So last week i found out that my husband is been talking to a girl ( coworker) we had a big fight.. He said that she is just a friend. Were being together for 11 years, now he said that there is nothing wrong to have female friends, and same for me that i can have male friends. I love my husband and i want us to be together for ever, i know that sometimes we have to make changes, in order to stay together and be happy. I told him ok thats fine. I am willing to accept something that i am not 100% happy to do but i love him. What would you do??