Are the foundations for a relationship important, or only the resulting friendship?

I'm sorry if the question is badly phrased but there has been something nagging at me for a while. I started university this year and met a guy, I really liked him and found him attractive and we ended up sleeping together for a couple of months. For reasons on his part it ended and a few months later when talking through our problems he revealed he only slept with me because as he phrased it, he was 'desperate'. Naturally, I was upset by this but a number of my friends have pointed out that as we are now friends, that I shouldn't mind how our relationship begun.
For me, it is a big issue as our friendship wasn't founded on what I thought was mutual liking for each other. However one of my close friends has said that as this guy and I are now close friends, which isn't due to desperation on his part, 'then what is the problem?' I wanted to see what peoples views were on how important are the reasons for a friendship forming compared to the resulting friendship, am I being irrational or do I have a right to be upset?

If it wasn't founded on the right things, it's gonna be unstable and will inevitably fall apart. As you have so seen for yourself. So what you need to do is tell him to **** right off, tell him you deserve a real man, a good man, not some immoral ego-driven prat, and bring that geeza to me so I can show man wagwun. :gangster:

That is interesting, I am glad I am not the only person who feels the honesty of the reasons for a friendship starting is important. xx