Your issues are with you, not with your girlfriend. You say that everything is good in your relationship, yet you still felt the need to snoop through her phone. If you really trusted her, you wouldn't have done that. You said you felt like a psycho control freak when you asked her if she was talking to someone, but you were ACTING like a psycho control freak when you went through her phone.
The fact is, you have no idea who this guy is. It could be someone who she met regarding a potential job. It could be someone she is trying to hire to paint a picture for you as a present. It could be a lot of things. But you are jumping to the worst case scenario. Why?
Think about why you have these kind of trust issues. The fact is she is either cheating on you or she isn't. But you will never be satisfied with either answer if you continue to have your own issues with trust.
Good luck.
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