would you rather be just content, in a relationship than be emotionally uncertain i.e VERY happy or VERY sad?

I dated a girl on and off both romantically and physically but for no longer than a couple of months at most. I attempted to step things up into a more serious scenario on a number of times but to no avail. Now the catch is that both our parents got divorced when we were older, so she saw what it was like for her mother and her family. and of course lots of ppl know that children of divorce are at higher risk for divorce themselves.also i was going through a rough patch psychologically while i knew her (call it a quarter life crisis), and i vented a lot to her, and she helped me as a friend, even though i expressed motivation to recover so i could be a stronger person for her. now she is engaged to be engaged to someone who, frankly, isn't very interesting but maybe more emotionally stable. now considering all things are equal would you (or do you think she) would prefer the steady choice instead of something sporadic given her parents history?