So it's a long story,I've been with my fiancé for 4 years now. I've known him for about 10+ years because he is my brothers best friend. Things have had their ups and downs like any typical relationship, about 2 years ago I caught him sending and receiving inappropriate and flirty text messages with one of his female coworkers who is married. Nothing happened really shed be the more flirty one but he'd never say no or stop. She'd get drunk and try to convince him to cone to the bar or discuss sending bude pictures to her husband.  We discussed it and decided to work through it.  The main problem now is that he's always had a fantasy that I said I'd be open to once we were married and living together and had more of an us routine if that makes sense. Im willing to explore my sexuality and open to try new things but I have a lot of trust and this is something I need to be eased into. His fantasy is more or less that he wants to watch me hook up with another guy, I'm more of a talker before I try something and feel like this something that we to verbally explore first and set ground rules first. I feel like right now is not the right time, we re remodeling a house together have 20+ acres of land to take care of. I've recently been pursuing getting another degree through nursing school. I'm 28 and he's 31. We re  supposed to be married in a year and a half.  Today I found out he's had a separate snap chat account that he claims he's been cat fishing for me. (Cat fishing is basically pretending to be someone else online and talking to them like your that person) I'm not entirely sure what to think or if I should believe him. My family is very judgy and conservative. If I end things or try to talk to them about this it will ruin his friendship with my brothers d my family will stop being supportive of me. I love him and care about him and his feelings in all this. I get why he wouldn't want to tell me he found all these pervy snap chat names on a forum and started snapping them. But the bottom line is he lied about it, lied for about 2 months, and then when I found it today he continued to lie and play dumb until he knew he was busted and then tried to explain. I need some legit help from ppl who have open relationships and the best way to handle this. I'm 100% out of my element and don't know what to think or feel other then hurt that he lied. I don't want it to turn into a situation like with his coworker. Is this something that he will continue to do because this is the second time he initially betrayed my trust? Or should I just chalk it up to him actually being embarrassed about his fantasies? Please help and please don't be mean.