How do you keep female friends?

I apologize if this sounds like a retarded question. I am quite retarded myself.

So.. I wanted to organize a get-together and I came to realize I have no female friends to call over. Several (male) people I have told already got really excited because they know me as a "womanizer", so they expect that there will be many girls at the party. Except that from all the girls I have known and talk to, I feel that only 1 or 2 would be comfortable enough coming over at this time. And it occurred to me that despite talking to and associating myself to several dozen girls per year, at any given time, I just actively interact with only like 1-2.

Generally, all the girls I approach and talk to is because I am sexually interested in them. A general rule of thumb of seddit (and mine as well) is that when someone rejects you, just move on. Brooding over and keep interacting with girls who don't like you the same way, hoping to change their mind, is only keeping you back. So when this happens, I cut all contact. This way, I usually end up with just 1 or 2 (or zero) girls I am seeing/talk at any given time. There are no girls (save a couple of edge cases this far) with whom we clicked so well as to seriously consider keeping them around as friends, despite being sexually rejected by them. However, these particular girls run away themselves when I revealed my feelings (maybe for the best).

So the actual question is this: Do you keep around girls who reject you? Is it worth your time? How do you maintain a friendly relationship? Don't you feel weird afterwards? Or do you befriend only girls who you are not sexually interested in?