It is SO much easier said than done but you have to step back and let her make her own mistakes. It's her life and, at 19, she has to go out and live it. Make sure you are supportive (not an enabler but supportive) so that you do not alienate yourself. If this ends as you predict, she will need you and need to know you are on her side. Don't bash her hubby - that will only create the "Romeo and Juliet" syndrome where she clings to him more. If she complains about him or needs to vent, listen and give honest, earnest advice but don't use accusatory statements. There are going to be a whole lot of "bite your tongue" moments. Steel yourself. It might not be the path you hoped for but you never know what will come of it. Perhaps you will get a grandchild that will become the light of your life. Or maybe they will both grow up and mature and actually make this work. Or perhaps she will move on from this marriage a lot wiser and will recognize Mr. Right when he comes along for real. Life is funny, who knows what will happen. Good luck to you and your daughter.