I have to say, as a person in an open relationship, you probably don't want to do the DADT thing, especially long distance (I've also been in a long-distance relationship, but not an open one). You spend your time wondering what he's doing, what other girls he's seeing, how he feels about them, if he still likes you, etc. And then your frustration comes out in short, angry bursts of crazy, like you showed on this thread. I've been there, my friend.
Much better to have everything above board. That doesn't mean that you need explicit details, but that you need to know what's going on and who he's seeing. Then you can rest easy.