How do you get over someone you still love?

you are not really in a 'relationship' are you? so why bother agonising over ending your flatshare and occasional conversions
i said this in another thread (or perhaps this one?):
'never make somebody else responsible for your own happiness'

HTFU and leave.

Wise words - and certainly true. On the other hand he is not just a flatmate and I care about him. But maybe this care is destructive for him and me as I'm afraid to tell him what I really think.

I know what's coming. He will demand and explanation over and over. I know I shouldn't sugarcoat but on the other hand I don't wanna go off on a rant and tell him that he is a horrible person.