Right, don't enter partner agreements with them, don't develop any kind of attachment to them, don't let them close, don't let them get too familiar with you (familiarity breeds their contempt) etc.

One foot out the door and don't let them close to anything that you would be upset with them breaking (they never apologize or take responsibility so just factor in how much bad they can do to you) and you'll be fine, they can even be an asset to the community and volunteer in exchange for kudos in the right circumstances.