Does it really matter? If she was seeing someone else is that going to make you feel better? Or change your situation? I get wanting to know why she broke up with you, but if she already said there was nobody else she will most likely stick with her story unless you had evidence to the contrary. All you're going to do is drive yourself crazy and cause more tension between you. You should be looking at how to get out of there and move on.
Does it really matter? If she was seeing someone else is that going to make you feel better? Or change your situation? I get wanting to know why she broke up with you, but if she already said there was nobody else she will most likely stick with her story unless you had evidence to the contrary. All you're going to do is drive yourself crazy and cause more tension between you. You should be looking at how to get out of there and move on.
The girlfriend is not the public, is someone he chose to be part of his life.
You may feel that way personally, but for adults that is an unusually long time to get to a fairly mild form of physical affection