Thanks both Black Unicorn and MrFarFromRight,
You both gave me good things to think about, and Black Unicorn, my guy, I'm going to start calling him Mr.C, surprised me with a coffee date this morning when I got off work, and we talked a little about the meeting this weekend. The sex/std stuff will definitely be a topic of conversation this weekend, but I kind of expected it since part of the reason they opened open their relationship to physical intimacy was because he was needing more than she could give physically speaking.
One question I have too is, if when we're talking and there's something I let them know I need to have in the relationship, but they counter with we/he can't meet that need all the time, let's say it's I need a date night every week. Does that mean that things are automatically doomed? or are there ways to compromise? I suppose this probably all depends on the people involved, but generally speaking, or possibly in your experiences, are people in poly relationships good at compromising? Personally I am a very understanding girl who's not super needy and really just wants someone to be with/spend time with once a week or so. But I understand that his wife is his primary and they have kids together. So yeah... any other thoughts or advice would be great!