Even though you believed through actions rather than words that your relationship was exclusive it appears that it isn't (wasn't). His dishonesty is now apparent and I would suggest that you do exactly what healingme4me said - run. This guy sounds like a complete user who is only interested in satisfying his high sex drive and as such has a stock of girls that he rotates through in order to feed his own selfish needs. Don't waste time trying to analyze him because from what you have written the answers are clear. He lives for himself, is dishonest, untrustworthy and is putting his needs before everything else. Consider yourself lucky that you have realized what he is all about and although it is a tough realization to acknowledge I am glad that it happened sooner rather than later so you can move on with your life. He's off to Colorado where he will undoubtedly continue feeding his sexual needs. That's a perfect opportunity for you to recover and heal from this bad experience. All the best x