He has been my best friend for 11 years. We have both had other relationships during our friendship and we have both been single at times during our friendship. Two weeks ago, we went on a weekend trip, (which we have done many times in the past) and ended up having sex (which we have never done in the past). We are both single and if we are being honest we have been attracted to each other for years. This has not affected our friendship. Is there a relationship potential here?