Why would I just up and leave the relationship simply because I'm suspicious of her behavior? Being suspicious and just completely not trusting a person aren't the same thing. I don't trust her if I look through her phone and actually find some dirt, I'm suspicious of her prior to looking through her phone and not finding anything.
If she's texting on her phone at 2-3 in the morning, I think it's a guy, it could be her sister or close friend that needs to talk to her about something serious over the last few days. She steps outside to talk on the phone, I think it's a guy, she could be planning a surprise birthday party for me. I trusted her to the fullest, but at the same time I didn't and still don't put anything past anyone. Humans are capable of some really, really f***ed up things no matter how cute and innocent they may appear. Synnen, if your husband or bf was exhibiting some shady, suspicious activity, you wouldn't get suspicious and care to do a little peek at his phone? Of course you can always communicate, but for some strange reason people who cheat also tend to not be the most honest.