Again, this gambling thing is subject to so many individual ideas of what is or isn't gambling.
So it is ok to stick a friend with your food and drinks, but not $5 or $20? I really don't get that.
Gambling only ruins the friendship if the person is a jerkoff to begin with (and you hadn't found that out yet) or they can't afford it (and then it's their damn fault and they need help for a gambling problem).
Know what else can ruin friendships? Women. Let's see a show of hands for who's giving that one up.
...
For another idea.. if I want to test myself against a friend of a certain speed, why not be willing to give him my money for an honest game instead of somebody I don't like?
If it is 3AM and I'm stuck in the snow, I'd just use my ex-friends' money to call a tow truck and/or a cab.

No, seriously, if you've alienated all of your friends, I'm pretty sure it's because you're a @#$%.