Five years is a long time to be with someone, and you won't get over it overnight. I was in a similar situation quite a long time ago, and my Dad said something which has stuck in my mind ever since. He told me I never had to 'make do' with someone who made me 75%, 85% or even 95% happy, because there would be someone, somewhere who would crack the 100% mark. Anything less is selling yourself short. When THAT one comes along, moving in will feel right, you'll enjoy the same things, and you won't have to do any soul-searching again.
A bit over-romantic, perhaps? Maybe, but you'd have your pride and self-respect intact that way. Don't just give it another go to see if it's any better next time - neither of you will have changed, and you'll end up miserable again.
You need a clean break and not to see him at all for a bit, in my humble opinion. Wishing you a 100 per center in the future! xx