When in doubt as to whether or not someone is able to get over themselves and whatever disagreement they may have had in the past with another, the question is often posed. Cool people just respond, "sure, we're cool." However, those with multiple personality disorders, depression, english majors or other mental issue will typically respond with a tirade as to why they find you despicable and how they'll never get over the pain they think you caused them.
Hey, dude, "We cool?"
yeah, man. we cool.