I don’t think this is a woman thing, it is unisex. Trust me, women wonder the same thing about men. As for an answer, make up anything. It is easier in the short run to break off any and all contact with someone rather than explain to that person face to face why you would prefer to spend less time with him/her. Of course, this is entirely disrespectful and very hurtful to the other party. When I was younger I once broke off all communications with a girl because I was selfish and thought it was easier just to let things fizzle and work themselves out on their own, rather than be an adult and tell her that I thought things were not working out. So – 1) not just a woman thing, and 2) it’s easier and less stressful (but very immature) to stop communicating.