Value In Fights?

I used to think that fighting was necessary--fighting, mind you, in the sense of me and my wife, or me and my friends, or "anyone with whom  I wanted to have a lasting relationship", however romantic that idea was, and I'm not referring here to anything physical. Two thoughts.

1) I thought that conflict really either engendered folks to each other, or propelled them apart, but that there couldn't really be mixing of the two once a fight was under way.  Once under way, moral questions became crystal clear.  I also thought the way you handled an argument said a lot about who you were as a person.  Perhaps it does.  But what does it say, exactly, and who is the correct interpreter?  Not the other party to the fight!

2) Fights as necessary to push out all anger and be done with it, to know "what people really think."  This was completely wrong though. When fighting we all say or do things that we don't mean, precisely because we're pushed and we amplify to hurt at times, when we're hurting.

Also, I reject the idea that we have to have fights to demonstrate that we will or will not be pushed around, and I do so by saying this: to what end?  Can't we find a place for relatively peaceful, even spirited, disagreements, or is everything supposed to be to the death?