Re: When do you call it quits?
No, I would not. I would do everything within my ability to try and fix the situation. I would also try to work on being happy myself. And yes, real relationships are far from what we see in Hollywood movies, as you say, there are ups and downs.
Knowing however that we cannot change the way another person feels even if we've knowingly done the best we can to help the situation, then I would understand contemplating going separate ways. But not before doing all I knew how to try and make things work.
Going separate ways should then be mutually beneficial.