My wife keeps leaving me and coming back. Can I divorce her the next time she leaves?

In this episode, Dr. Betters answers the question, "My wife was diagnosed with bipolar [disorder]and she refuses to admit it; therefore, she is not medicated. Over the last 4 years she has left me (and our daughter) several times. Each time she tells me she wants a divorce and I tell her I don’t want a divorce, so she leaves. Then, a few months later, she apologizes and wants to come back home. Every time I take her back because isn’t that what Christ does for us? My question is, would it ever be okay for me to say, “enough!” Can I ever go through with a divorce?"