For me there's several rules in dealing with disrespectful people -- whether in the office or just in everyday social situations. If/when the situation becomes intolerable the first thing I do is make my feelings known in a gentle but firm way to the offender. If that does no good I make it a point to just avoid the offending person as much as possible. If avoidance becomes impossible (you're dealing with a pushy, overbearing type) I'll finally make my position clear, such as: "We don't seem to have much in common nor is interaction between us fruitful. I suggest we just go our separate ways, tend to our own personal business and avoid each other at all costs." I've done this and it works with some -- others just become incensed because you've addressed the problem and refuse to play their game. Does it work every time? Obviously not but it'll go a long way to get the person off your back.