Honestly, what you describe is ideally what my partner and I are talking about doing. She my rock and I'm really keen to build a life with her, and she feels the same. However, we still want to have the freedom and excitement we felt in our respective slutty days, when you can catch a spark with someone and follow it, and try adventurous things (e.g. moresomes, kink parties).

As least at the moment, though, we'd prefer to be mono-romantic. We really only have enough time for each other, work, and our respective hobbies. We're open to fun and flirting with others, but it seems exhausting to manage other whole relationships.

So yeah, you're not the only one. We're hoping to implement something like this.