How do I get rid of that all or nothing mentality?

Develop a "good enough" mentality.

Learn to compromise with yourself. Nothing is black and white, everything is grey. 

You can't I think must be your way of coping. Blood strike must be right though maybe listen to him.

It probably happens in reaction to your emotions running out of control. Learn to tame them and it'll go away.

You should know we can not have it all.

You've either got it or you haven't.