I had the same issue when I first played. Now, if anyone calls me or any of my friends a hacker, I usually do one of the following:
1) Tell them to prove it or be quiet. [Although sometimes "be quiet" comes out as "s-t-f-u"]
2) Say "Demo it, I don't care."
3) (the fun one) Try and accuse THEM of hacking.
The bottom line is that if you hack, you will get caught by an automatic cheat detection system. If you don't hack, there's absolutely nothing to worry about.
*Didn't know "s-t-f-u" filters to "be quiet"