Not getting away for vacation, or getting away for the weekend, but getting away from that person at a networking event who just ... won't ... end the ... conversation.
I talked to one of our members who is a little bit new to networking (but doing a great job so far). She had a good time at one of our recent events, but mentioned that she had a hard time getting away from someone who was monopolizing the conversation.
She did the right thing. Very politely, but honestly, she told the person that she had to move on to talk to some more people. I told her that was perfect - you should always be honest. Don't feel bad about telling someone "I really have to keep moving" or "I need to meet a few more people". That is the truth, even if the deeper truth is that you've heard way too much detail about their personal life or feel like you're getting the hard sell and that's why you have to move on.
Remember, too, that these people might be clinging to you because they feel shy or uncertain and you're a safe haven for them. So instead of "ditching" them, introduce them to someone else and help them feel more comfortable.
Socializing is something everyone should learn to help them with "mingling" and events, but too many networking books make the mistake of treating the social skills like they are the only skill set you need to be an effective networker. It's certainly important, but only the first level. The member who I talked to has one of deeper skills, which is relationship building. So keep it up A.B.!