And, what happens if it doesn’t work out? Rather than considering the potential positive outcome, think of the current situation you’d be ending. I think it can be often weird and reductive to end relationships because you want to start another, esp when there’s no other reason. If you want to end the relationship, end it, but you’ve made your commitment and you should stick to it until you change the circumstances.
Nobody is going to tell you to stay in a relationship you don’t wanna be in, but you shouldn’t tell yourself that jumping ship is the best way to exit. Also if you’ve been together that long, lowkey be single for a little! You can learn a lot about yourself. Breaking up should be a decision that should be about YOU, not any potential partners or “not wanting to break their heart.”