>I have an ex colleague who was very helpful to me when I moved here. He looked out for me and even invited me to his home for dinner many, many times. He hooked me up with local groups, etc, etc. He even occasionally still asks me to go to some local events these days. But I'm pretty sure he hates my guts.

Why would he do these things for you if he doesn't have to? Obviously, he doesn't have time to do this for everyone, so does he have some incentive to expend this energy on you? Does being nice to you help him out in some way?