Another thing you should consider is that the "real Marine Corps" is nothing like what you have experienced thus far (if it were no one would stay in for 20). Consider the whole OCS thing like rushing a frat, of course it's going to suck but once you get the frat life is way better (ie people actually treat you well, do what you say, repect you, etc).
I used to be in your boat durring my senior wondering if I should or should not accept my commission (this is one of the drawbacks of PLC). In the end it came down to considering what the hell else would I do that would be as rewarding/fun? Most of my civilian friends are in entry level mangement positions, grad school, law school, or unemployed and none of them seems to really like their job.
The way I saw it is that you will be a Marine (which is cool in and of itself), you will get paid, you will gain respect, you will have excitement and experiences you cannot get in the civilian world, you will get GI bill, and you only have to give them 4 years. So when you get out you will be 26, have awesome leadership experience, be a veteran (if our current optemp keeps up), see some truely crazy things, be wanted by women and envied by men, and have $40,000 given to you for grad school, and all the while take approx $100,000+ and 120 days of paid vacation. Doesn't sound like such a bad deal to me.
Semper Fi,
usmcecho4