Is it normal that i encourage my husband's affair?

2 months ago my husband admitted to falling in love with a coworker. He said he had never connected with anyone like this before. My heart was so broken that I said he could sleep with her as long as we could have an open relationship. He agreed, had sex with her all week, then went back on his word and said he couldn't handle me being with another man. Now I feel trapped in the marriage because I don't love him anymore. We have children and he's a terrific father. I don't want to separate. It's easier for me to stay. When he told me he would end it with her I told him to keep going. I feel like I'm just allowing it while I bide my time. Maybe he'll fall deeper in love with her until the kids are older?