“I have been married for more than 20 years to a man who loves me, who is great, and whom others all asdfadsf ”

I have been married for more than 20 years to a man who loves me, who is great, and whom others all love. We have children - all teens.nThere is nothing wrong with him, but I don't love him any more and don't want to say married just for the kids. Though, I could handle it until they all go to college.nShould I stay until then? (I don't think the kids or he notice so they are/ seem happy.)