There's always the argument when a couple 'breaks up' or gets into a really big fight and one of them cheats. Is it cheating? Is it not?
It's like on Friends when Ross and Rachel (soo cute) took a break and Ross slept with that copy girl, and the next day Rachel wanted to get back together.
It's sorta the same thing as season 1 in a way. I don't think Dan cheated, it's a blurry line but I wouldn't call it cheating..