I haven't observed the dating habits of very many people so I will just speak from my own experience. Having broken up with my first boyfriend, I was single for a period of about 8 months. However, my first boyfriend and I had not been very much in contact for the previous 2 years, and during that time it felt like a relationship in name only.
My second boyfriend and I were together for about 3 months before I went overseas during which time we also began to drift apart, again giving the sense of only nominally being in a relationship. He finally broke up with me a few months after I returned. I realized afterward that I really hadn't known him at all and that we had never been very emotionally close. A few weeks later I met my current boyfriend. Compared to my first two boyfriends, he and I are much closer and communication is much easier.
My point is that not all relationships are the same and that in some cases there is very little connection to the point that there is less to "get over" as it were.