Edit: The day(s) in question happened a few weeks before we got back together. I'm aware, I'm not upset about when, I'm upset about who and why it was hidden.

Edit 2: we are enrolled in couples counseling, our first session is in 2 days. I suggested it to her in hopes of a solution, either the truth or deleting it from my mind completely.

We met a little over a year ago as of today, and basically got serious and started dating immediately. It was like "love at first sight" and all that. We stayed great until January, so roughly 4 months of dating. We ended pretty rocky and long story short, we were living together at the time and I kicked her out and broke things off.

Fast forward to now, we have been engaged for almost 2 months and it's going nowhere but downhill because of this.

We stayed split up from January until June. We still talked to each other almost every day and she would actually come see me(she lives 3 states away) and we'd talk and go out to eat and stuff.

Well shortly after we rekindled the relationship, about 2 weeks actually, I saw a video on her social media of what looked like to be one of my best friends. So I text her, asking "when is the last time you talked to Z?(we'll call him Z)

Her response- "He called and asked what I was doing and if I wanted to go on the boat and I said sure"

He lives 4 states away from her....

I ask her to show me the texts and messages between them, and they were talking in pretty intimate ways pretty much as soon as I kicked her out of my house. There were a few that really left me with a gut feeling that something else happened other than just a boat ride. She put all the pictures and videos from that day in her hidden album on her phone, when I asked why they were hidden, she says "I don't know, I didn't even know they were in there"(Remember this for later)

She swore up and down that nothing ever happened between the two of them, nothing physical whatsoever.

I ask her why she didn't tell me about that whenever I asked about what(who) all the did during the time we weren't together. She said "I was gonna tell you at some point , I don't know why I didn't tell you already"

I dig a little more and found that she stayed the night at his place. I ask her again, what happened between the two of them, she says "nothing, we just went back to his place and sat on the couch and watched a movie. Then he went to his room and went to bed and I slept on the couch"

I have asked her a few times since then exactly what happened bc it's always been in the back of my head that nothing really added up, and every time she tells the story again, I get new info.

Basically, I have found out:

-he "tried to do things" with her but she "kept pushing him away" -they BOTH slept on the couch together -she admitted to hiding the pictures in that album because she didn't want me to see them(still are in there as of last week) -she went to his place a 2nd time and nothing happened between them then either, apparently

I just want the whole truth and I honestly do not feel as if I'm getting it from her.