Question
My husband finds it necessary to protect his mother from me. If she says anything about me, he agrees with her and afterwards lies to me about what was said.

When I confront him he says that this marriage is not worth it and he wants to end it.

Why?

Answer
You'll have to talk to him about that.

It sounds as if the conflict between you and his mother, or perhaps the degree to which there is interference in his peace of mind because of the conflict, has got him thinking that it's not worth carrying on any more; he can't divorce his mother, so he threatens to divorce you!

Even when you love someone, sometimes living with them can be so difficult that you decide you'd prefer to live without them.

I'm sure you understand that in a general way, even if you can't see how he's got there...

If you don't want him to leave, then maybe you can start exploring ways to channel the tension between yourself and your mother-in-law differently. I don't say that what you have been doing thus far is wrong, since I haven't been there! But one can see that whatever it is, it is not working to keep you and your husband together.

So it's on that fairly secure basis that one can say it's high time for a change.

If you feel stuck and don't know where to go next, I'd suggest that you consult a marriage therapist. Your husband may well not be interested in going, but if he rejects the idea, go by yourself anyway and start the process.

You may be able to "invite him in" later on, and if it all does end nastily, at least you'll have some support.