Leave boyfriend with red flags before he becomes husband

Q. My boyfriend and I have been together for five years. We are in our mid-to-late 20s, and have been living together for a year. We generally have a great relationship, and we have talked about getting engaged soon.

However, I'm not sure if staying with him is the best decision for me. He was diagnosed with ADHD and oppositional defiant disorder (ODD) as a child, and I feel as though this is really detrimental to our relationship.

He gets annoyed and frustrated extremely easily, which often leads to a fight in which he gets very angry, and tends to hit or throw things (though I am 100 percent sure he would never touch me, he only throws and hits things like pillows).

I grew up in a very peaceful household where there was never any violence, so dealing with his anger is totally foreign and scary to me.

I know these are symptoms of his ADHD and whatever adult ODD is or becomes, but I am at a loss of what to do. He has taken medication off and on in the past but doesn't like how it makes him feel.

I don't want to leave him but I can't imagine a future with both him and these symptoms. What do you suggest?

A. Leave. Either you aren't up to this challenge or you don't want to be, and that's all you need to know, because choosing a life partner isn't about being open-minded or fair or noble. It isn't just about loving or being in love, either. It's about an unflinching estimation of what works. "Foreign and scary" five years in=Does Not Work.

We can stop here, but I won't, because:

• Your "100 percent sure" requires me to say, no, you aren't. Dumb luck excepted, good decisions aren't possible unless you admit what you can and can't know. Facts = certainty. Future = conjecture.

• It's important to clarify that a serious diagnosis is not the end of hope for a committed partnership.

It just means added diligence for it to work: The person with the illness needs to manage the condition effectively, and the partner needs to be temperamentally suited for and at peace with the challenge. You and your boyfriend are apparently, right now, 0 for 3.

• People who don't feel ready to leave often tune out people who suggest it. If that's you, then please at least heed this: You owe it to both of you to express your misgivings to him as you have to me.

Tell him his short temper and rages scare you. Tell him it would mean a lot to you if he made more of an effort to manage his condition - if not through medication than with therapy and other adaptations.

The National Resource Center on ADHD, (800) 233-4050, and its parent, CHADD, www.chadd.org, are rich with suggestions.

Then, as you assess the result, don't flinch.

• Email Carolyn at tellme@washpost.com, or chat with her online at 11 a.m. each Friday at www.washingtonpost.com.