I read this post which I think represents the views of a lot of women. Apparently her bad experiences with men has made her pessimistic about relationships in general.
Instead of thinking men can't be faithful, wouldn't it be easier just to weed out the cheaters before you gave your heart away? This is why not allowing a relationship to proceed too fast can prevent you from falling in love with the wrong man.
How do you keep your relationship moving slowly? Simple, don't allow him to spend as much time with you as he would like.
I know that doesn't sound like much fun for you either, but unless you see how he responds when he doesn't get his way ( not seeing you a lot), you'll never know how he will act under the pressure in the future.