Okay wow, well let me try this.
Did you set up when he's supposed to tell you? I ask my boyfriend if he's interested in anyone, or why he hasn't asked out the girl I KNOW he likes at work, but we've known each other YEARS now.
We've also discussed, in length, at what point I NEED to know things and want to know them. I NEED to know if there's sexual endeavors, for safety reasons. I LIKE to know about the flirting, and that he's talking to someone or going out. HOWEVER, it's not required. I like to know he's happy that he's dating, but I understand everyone has a different level of privacy they are comfortable with.
There are times I've been told just someone he is interested in but not asking out just yet. I've also been told after the fact that there was someone he was interested out, went out a few times, dinner, movie, and it didnt' work out.
He was CONSIDERING having sex with someone else and you feel it's a breach that he didn't tell you. Perhaps he was planning on telling you IF it became something? Perhaps he doesn't feel the need to tell you about every little step in a potential relationship. Maybe he felt it was like jinxing it if he tells you every time and nothing comes of it.
Just, another thing to think about.
What you feel you NEED to know and what you would LIKE to know are two different things and there's a lot of in between.
Me: Late 30s pansexual poly.
DH: My husband of 19 yrs and father of 3 teen girls.
DC: LDR of +4 year