Need some relationship insight, can you relate?

Looking to talk to anyone who may be going through or has gone though what I m currently experiencing. My serious boyfriend that I live with will NOT stop doing things behind my back. He s in the military and has a history of cheating/hiding who he s talking to from me. I ve stayed with him because he s never physically cheated on me, had stopped talking to other girls, and has been very honest about everything he s done in the past. He s also been very honest and "seemingly" transparent with who he talks to since I caught him almost a year ago. However, I recently found out that he s been deleting messages on fb messenger between him and people from his past (they appear on the iPad when the app is opened then disappear because he deleted them from his phone app). One example is his prior female boss who he (and his ex wife) were close with when he was stationed at another base. Even though this woman is married and lives in another state, I m confused as to why he is being secretive with their messages. If he has nothing to hide, why does he delete them and not mention talking to her? She also friended me on Facebook recently when I ve never met or talked to her the entire time we ve been together (over a year and a half). If anyone can shed any insight or wants to share their experience please message me! I m desperate after finding out he plans to propose to me… Questioning everything. I m looking for honesty, regardless of how hurtful it may be. My Kik is enlightenme0

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