Marriage counseling

So my husband and I decided to start marriage counseling, our first appointment together is in two weeks. We have a 2.5 month old baby girl, our first. And two weeks before I gave birth I found out he was messaging another girl... since then our relationship has been pretty rocky but have decided to try everything to make it work in order to stay together for our daughter. I’m excited to start counseling and moving forward in our lives. Anyone have any experience in going to marriage counseling? How did it work out?