How denial boosts fantasy

One thing I’ve noticed when being teased and denied often for days/weeks at a time, my fantasies go through the roof. I start wanting and sometimes craving things I know aren’t rational or probably wouldn’t enjoy if I wasn’t so damn horny. Lately I’ve been feeling like I’d be okay with her sleeping with someone else as long as I was able to be there or watch or be Involved somehow. This is something I’ve been completely against for 40 years. Now it seems feasible. Or wanting a three some. I’ve never been into it but now I fantasize about it all the time. Even if in the fantasy I’m caged or still denied. Or even forced to do something I’m not into. It’s more about the power exchange than the act itself I guess. My question is, I’m sure others have felt this where hard limits become soft limits and soft limits become desirable, but has anyone acted on these horny fantasies? Did you regret it later after reality set in? I’m starting to think I should mention it to my gf but if she does want to push the boundaries of our sex life im also thinking maybe I shouldn’t cum? Maybe I need to stay in this headspace or I’ll lose interest and regret what we would do. Anybody have experience with this?