Having trust issues. How can I deal with them?

I’ve been dating Amanda for just about a year now. I love spending time with her and she makes me feel very comfortable with myself. About six months into the relationship she had a male friend in town that she hadn’t seen in a while. She told me she was going to grab a drink with him and catch up on old times. I had no problem with this, but I found out later that he stayed at her place. I expressed to her that I was very uncomfortable with that and I felt betrayed. She convinced me that he only stayed on the couch and that I had no reason to not trust her. I told her as long as she never lets any male friends stay at her house again that I’d let it go. Unfortunately, I couldn’t let it go completely. I did something I am not proud of, I started to check her phone messages. This only lasted for a few weeks and I stopped. The next five months or so I stopped worrying and tried to enjoy my time with her. It’s been good. A month ago she was using my computer and logged into Facebook and forgot to log out. She was using a different browser than I usually use so I was unaware until two weeks ago. When I opened this browser it went to her Facebook. I was curious and looked at her messages, not proud. She had recently reached out to a guy a told him that she used to have a huge crush on him while they were in school. The next day the message was gone. Since then she has reached out to another guy and again expressed to him that she used to have a huge crush on him. They flirted back and forth for a few days, but eventually she deleted the messages. Since I’ve been dating her some of her stories she tells me don’t add up. I feel like she lies about little things that don’t matter, but it’s not often. She typically is really fun to be with and someone I can talk to and vice versa, but I can’t shake these feeling. I really want to talk to her about my trust issues. At the same time I can’t really tell her that I’ve been snooping. Is there a tactful way to tell her that I can’t trust her without exposing myself?

You need to take your thoughts back to when he stayed on her couch. It's irrelevant whether he actually stayed on the couch or not..what is relevant is that if she had any respect for you and he had any respect for your relationship together with her, he wouldn't have stayed overnight. Furthermore, her FB messages with 2 other guys reinforce her attitude towards your relationship. She is either with you or she's not and her actions are telling you that while you guys may have fun together etc, she really isn't 100% with you. You have trust issues which are very real and in this sense, you have no business expecting her to commit to you. You need somebody who shares your standards and values no matter how comfortable you feel with them. They need to mirror your expectations of a true relationship and they also need to respect it's boundaries. Your actions of checking her phone etc are telling us that your gut instinct is kicking in....listen to it.

Why are you still worried about being "tactful." Based on your story, it's actually her actions that led to your well-justified suspicions. The fact that she'd let another guy stay at her place and has been blatantly flirting with other guys online should be your warning flag that something is up. Be straight and lay down everything that you know in front of her and if you still want to continue this relationship, then tell her that this behavior has to stop. A word of warning: it seems like your partner has a serial cheating problem though and I'm afraid that her kind usually do not stop even after getting caught once or twice.

I know it would be hard hearing this from people, but the fact that she is deleting messages is not a good sign. If she is deleting them, it's because she doesn't ever want you to see them...she is feeling guilty and knows that she is doing something wrong. Hence her deleting them. I am in a relationship and if I told someone else that I had a crush on them I would feel like I am doing wrong by my partner. See how you go for another week or so, if you are still not trusting her you have to confront her and tell her.

Hey SUSIEDQ, She is nice to other guys in public which comes off as flirty, but it doesn't upset me. I am confident and secure while I am around her, it's just when I am not there I can't read the situation. Another thing she does that I find strange is she'll tell me that she is going to travel somewhere, but then never go. For example, she will say, "Hey I am going to head to New York next weekend and meet up with some friends." I'll respond, "Sound fun." Then she'll never go. This has happened at least 5 times since we've been dating. I find it very strange and don't know how to feel about it. I know she cyber flirts with guys on facebook, specifically old crushes. It is very possible that he slept on the couch, the only reason it make me very uncomfortable is that she lives in a studio apartment. So he slept only a few feet away. I am 27 years old and she is 31. She constantly throws my age in my face and acts like it is a big deal that we are 4 years apart. I really don't see much difference in our maturity levels. She is completely unaware that I know any of this or have these feelings. I want to express myself to her, but don't want to come off as "an immature 27 year old."