This is one a lot of people won't feel but I'm going to try to help you understand. When you living that life, especially in Hollywood, you meet so many people.
Think about it... let's say you go out four days a week. In those four days you might meet a group of women from out of the country, another group of women from out of town, a couple college girls as well as some girls who don't come out much but probably got drug out by their friends tonight.
The girls that you meet from out of town probably just want to party, so if they're in town for four days you might end up spending four straight nights with that group of girls. But they cycle out at the end of the week & a new roster comes in & it's the same thing rotated over & over again.
Also, people just fall off the map sometimes. People get girlfriends/boyfriends or maybe the occasional job or some people just end up moving back home because the city got too crazy. Everything is so fast so in three months the whole landscape of everything might have changed. The doormen at spots might be different, your favorite bartender might be gone... anything is possible. So a Hollywood 3 months is like a normal person's year because things switch over so fast when you are living at that speed. Everything & everyone, for the most part, is temporary.