Let me ask you this... who cares?
My post will be a bit in your face, but I assure you it is said with love, and I promise you we will find a way to get you out of this.
By the looks of your post, it sounds like you wanted a girl, failed, and now shes on to bigger and better things. It reminds me of a child who didn't get what he wanted for christmas and is now complaining because someone else got it.
There are two separate issues here: 1- you, your relationship to the girl, and your sense of entitlement. 2- the girl and the other dude and how they are treating you.
1- You have a sense of entitlement over a girl that is NOT YOURS. You kissed twice in 6 months and what now? Your expecting her to get on her knees and swear undying loyalty to you? True players understand one thing: The ONLY thing they are in control of is they're own actions and behaviors, NOT those of others. In other words, you cant control her, let go of that sense of entitlement. She isnt yours and if she left you for something else, it means you did something wrong, and need to work on yourself some more. So to answer the topic question of your post: Do you think she did something with that guy? My answer is WHO GIVES A FLYING FUCK? You do NOT have time to obsess over a girl you arnt fucking. Its none of your damn business what she did and with who. Get over it, work on yourself, and allow yourself to grow into a better person
2- The way they are treating you is fucked up. It isnt right and no one deserves to be messed with. That being said, there are two courses of action here. There is the negative way: You can lash out, get mad, tell the guy to fuck off, or wine to the girl in the most pathetic of ways "why are you being like thisssss?" But that wont accomplish anything (been there

). The second course of action is to rise to the occasion. Treat them with respect, leave them their privacy, and move on to other things. You work together, you dont live together. Let them be happy together (assuming there is something going on).
The moral of the story is: Complete yourself as a person, completely independent of others. Walk around with a smile, not to show others that you are happy, but because you TRULY ARE HAPPY. Dont envy others for their happiness, learn to create your own. Dont dwell on the past and cling on to little things, and dont actively look for insult where there is none. Practice the philosophy of love and help spread it. Talk to women because you love them! You love their beauty, their femininity and everything about them. Your smiles are no longer faked, your lines are no longer forced and nothing you say is a lie. From now on, there is just you, women, and the beauty of life. You will live a much more fulfilling life if you follow these simple principles
All the best
Love and lots of it
TheMack
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