I agree with cbox. I think that knowing can be helpful. For years I had know idea why I would act or react the way that I did. After learning my dx, and doing research on it, I was able to 'see' that many of my reactions were affected by my dx. It helped me to adapt in different situations, and especially relationships. (my first marriage ended shortly after I got dx'd, but am in my second marriage and will be celebrating our 8 year anniversary next week.)
This was of course helped by therapy. I learned how to act and react differently in many different situations (of course using what I've learned is a bit more challenging), but it certainly helps.