I desire something ENM/poly & my monogamous relationship is ending. Anyone had the same?

I have this desire for a lifestyle that is focused around non-monogamy. I have come to peace with it (not that it’s bad, it’s just fairly new to me) and after discussions with my current partner of 3 years, who does not desire it, it’s clear that a final conversation needs to be had so that we can part ways and find a relationship style which suits us both.

I know people get criticism for saying that they “need” ENM or for treating it like an orientation. And I understand that ENM/polyamory is a preference ultimately.

But when I said I feel that I feel like I “need” this, it’s because the desire really is that strong. I’ve had a few different partners who have been wonderful, cheated on an ex before despite the relationship being great and now have an amazing partner but I just feel like something is missing still.

I have ADHD and I adore connection with people. It drives me and gives me energy. I have always pulled different types of energy from different people in my life - be that platonic, sexual, familial, etc.

I really thrive off of mental stimulation, human connection and variety. And I feel that a more open relationship style is something that would suit me better. This isn’t about sex solely, it’s about connection.

My partner and I still have sex multiple times a week, we do lots of fun things together and we are paired well. But there are so many cool people and experiences out there that I am driven to try, and I cant deny that pull anymore.

But it does feel slightly terrifying. I’m leaving someone I love (please spare me the “you’d just be monogamous then if you loved him”), a very secure set up and changing my whole attitude to relationships because of this core desire of mine to have freedom to have different connections and experiences and to draw energy from, and give energy to, multiple sources.

I feel people must have this situation all the time… but I feel slightly overwhelmed (and devastated tbh) because although deep down this feels like the right path for me, I can’t help that feeling of shame that I can’t remain monogamous long term/don’t want to. And it does feel like a huge change to make and I know it will be brutal at first.

I guess the question is - have you left a monogamous partner to switch to openly dating, ENM, being poly, etc and what was your experience?