My girlfriend returned from a short separation

by novaguy
(asheville, nc)

My girlfriend and I were apart while she went to school abroad. Since her return she has spent hours and hours talking via e-mail and skype to another man.

When I confronted her about it she said they were just "friends". She says she loves me and I should not be worried.

She left an e-mail open and though it was wrong I read it, and she told him that she had no feelings for me and she was just pretending.

Again she says he is meaningless, so how do I confront her and get her to tell me the truth?