Living in Southern California has its perks: laid back life-style (at least compared to the East Coast where we are originally from), beautiful sunny weather many days of the year, beach living, proximity to many interesting places to where one can take day trips, etc. However one downside is that many transplants come here to live for a few years taking advantage of all this place has to offer but then end up leaving. Some reasons include the expensive housing/cost of living which deter people from ultimately settling down here, others who came here for graduate school and after they finish their studies they have go wherever career opportunities take them. Also there are those who want to move back to hometowns where their families are especially once they have children, etc.
Dean and I plan on staying here for as long as we possibly can (though we always joke about moving to Texas where we can actually afford to buy a house). We love it here and pretty much prefer to rent here than buy anywhere else. We are willing to pay the "sunshine tax" (high cost of living) in order to raise our family here. But it still doesn't make it easy for us to have to say goodbye to so many of our friends/acquaintances who have come and gone. For example, just this year I have had one good friend move to Oregon, Dean's good friend moved to Michigan, a couple that we are both friends with moved to Washington State, and another couple that we are friendly with is moving to Northern California.
Since becoming a mom I have made a concerted effort to make new (mom) friends. I am always asking, "So do you plan on staying in the area or are you most likely leaving at some point?" It turns out that many of my mom friends are on 2 year, 5 year etc. plans here, meaning they also want to leave at some point as well. It is a little disheartening to know so many people want to move away but I totally understand, especially if they want to expand their family. Being in another location closer to family where the cost of living is less, definitely makes having a bigger family a lot easier.
Before I used to feel more down about the situation but the lesson I am learning is to just really enjoy the friendships with people while they are still here and to just trust that if/when people move on I will be able to meet/make new friends when needed. Essentially I am just going to concentrate on the present and not dwell on what could (or might not even) possibly happen in the future.