How do you break someone’s heart gently?

This guy loves me.. we had been dating since last year & he cried to me tonight. He told me he’s never felt this way about anyone. I know what it’s like to have your heart broken by someone you love. It’s the worst, life-sucking feeling ever & I wouldn’t wish it on my worst enemy.

I tried working out our differences, but we have such different mentalities, that it simply didn’t work & frankly, I’ve given up on our relationship working out. I don’t want to put him through that kind of pain, and I also can’t give him false hope that we will be together because I have already emotionally checked out. What do I do??