Over the years, I have made friends with various people, both in real life and online, that one would not expect. And there's a reason for that.
I don't give my friendship easily. Now, that doesn't mean I won't be friendly, it just means that if I consider you a "friend", you're family. I'd take a bullet for you, and I will defend you unfailingly in front of others.
But that doesn't mean I'll agree with you. In fact, in the circle of people I consider friends, I prefer to include the ones with whom I disagree the most.
Why is that? Because I'm a rather arrogant creature, and I know it. Early in life I tried to stop being so arrogant; as I grew older, I saw that it had certain benefits, and that the best way to deal with it was to keep it in check. And sycophants most definitely do not help keep it in check.
The kinds of friends to whom I generally tend to gravitate, do.
I prefer the kind of friend who can say "bugger off, Gid, you're an idiot!", then go out and have a couple of beers with me directly after. I want the kind of person who realizes that philosophical disagreement doesn't have to mean rejection of the individual, it just means that the two of you do not agree. Who can respect my boundaries but who isn't afraid to cross them when I don't respect the boundaries of others.
In short, the HONEST kind of friend.
Nothing annoys me more than a phony. If you have a problem with me, I want you to tell it to my face, not blab it all around town. Talk TO me, not about me. I've experienced great personal growth through friends like that, and I love them and cherish them. ESPECIALLY when I disagree with them. For it is those disagreements that show that we both respect each other enough to say what we really believe.
Personal attacks are another story. One can disagree without being abusive. One can disagree respectfully (although I am of the opinion that a few heated disagreements are good for the soul). But when you come after me personally, then you've crossed the line (this includes those who are so inclined as to state that I'm going to Hell; you CANNOT know and have no right to sit in judgment).
I love my friends broken and imperfect, because that's just how I am. Broken. And imperfect. And somehow in that brokenness is the beauty of God's creation.