On another thread, someone said that multiple dating is now common, where people will be dating more than one person at a time. I have been in my current relationship for 4 years, so am willing to be told that British culture has completely changed in that time, but I don't think so! I have a friend who uses dating websites. She certainly has a lot of first dates, but even she is not going and having third and fourth and fifth dates with more than one man at a time, and I would think she was treating them pretty badly if she did.
I know a couple of guys who do this kind of thing, they even get to the stage of sleeping together, meeting the parents, and they are still seeing numerous people. Without exception, the women have always been very upset when they found out, but the men think they have done nothing wrong saying, 'aha, but we never said we were boyfriend-girlfriend/exclusive, so this was fine.' I have never had that kind of conversation with a boyfriend, but simply assumed it was mutually understood that if we met, went on a date, liked each other and decided to go out again, then that was it, we were dating, and we wouldn't be pursuing any other avenues. It might last a few more dates, or it might go on to be a long term relationship, but for that time, we were 'exclusive' and I would have been mightily shocked and pissed off if I found out otherwise.