Gay Redditors I need some advice

I'm on the verge of leaving someone I love after 7 years because I miss having meaningful sex and I'm an emotional burden. We have shared a life and built ourselves a safe place, grown, laughed and learned heaps about life together.We are never seen or expected anywhere just by ourselves. We spend all our time together, however around 3 years ago we realised we weren't attracted to each other anymore, we felt we had become more like brothers and also craved hooking up and basically, ripping the clothes off other fellas.This did come with its challenges, however we felt like we had cracked the code, we never got too jealous or possessive and allowed each other the space to "outsource" so to speak. Like being best mates who hugged...Lately after we have both graduated his life has seemed to improve, and mine has deteriorated. I'm currently going through a rut, I feel like I'm literally bad at every single thing I do. Being around him should be inspiring, it should be making me feel I'm successful by default. However I'm feeling like the more I know, the more I try, the more I have ambition the more disappointed I become with myself. And once when I was hopeful for a rewarding future I thought my small, often random and quick sexual encounters would suffice.However of late on one encounter it ignited something in me, and it doesn't take a scientist to know that sex can be truly amazing when you have it with someone you like, more than just for their ass and dick. You actually dig them. I'm tired of feeling empty. And it's making me wonder...am I just chasing the "honeymoon" period, am I just missing passion? Is it wrong to want those things? I know I have been influenced by the fact I have a small crush on someone, I just don't want to put to rest this craving. I know it will make my partner feel like shit if I keep doing this though, he knows and it does already, and now I feel like I can't even enjoy outsourcing casual sex...I know I will break my partners heart when I leave, he knows it is looming, we have spoken about it. The last 6 months we have had many exhausting late-night conversations before bed where we come to no resolution...I'm an emotional burden, my anxiety and depression is making me emotionally abusive. And woah, this post is just becoming a trainwreck really. I have a lot of fear that I may be making a terrible decision to go it on my own...Perhaps we just need space...to work out what we really need out of life and relationship. But I suppose what I want to know is if anyone has an almost a-sexual gay relationship before and how did they put that craving/curiosity to rest. Or if not tell me, can people stay truly monogamous without fear of missing out.