When you're playing heads up you just have to be brutal. He pushed you off the pot way too many times with nothing. I think you need to make some big preflop raises (ie to 1000) and then push allin on the flop. 80%of the time he doesn't have anything and he is just stealing the pot. The thing is, I'm not really used to this, because the blinds are very small and the stacks are very big. I'm used to 5000 vs 5000 chip stacks and blinds of 250/500 or 500/1000. That's much, much bigger than what you're playing - so my advice probably isn't that useful. But be aggresive in 1 on 1.