And trust me, as you get older, it's not that big of a deal anyway. (Although I know from experience that it IS a pretty big deal when you're twenty, but that will change)
Bingo. I know you don't believe it, but trust me it is true. The day will come when you really won't care anymore. It's a combination of maturity and your hair becoming so thin and looking so bad, that it's a relief to finally be rid of it.
I'm going to offer some advice that you're probably not going to like. I know I would have dismissed it when I was 20 years old. But if you're willing to take a leap of faith and listen to some older guys who have been through what you're currently experiencing, we can make the transition a lot easier for you.
First of all, stop obsessing about your hair loss. You didn't say how advanced your hair loss is, but the best thing you can do is get a buzz cut as short as you feel comfortable with. And as you lose more hair, get it cut shorter. Don't be afraid if some scalp shows through the hair. I remember how I used to dread the day that I'd have a bald spot that couldn't be camouflaged. It's far better to let a little skin show than to try to cover it up. It projects a more confident image and tells the world that you've got more important things to worry about than something as superficial as your hair. Eventually when you get to the point where your hair is buzzed extremely short, shave it completely. It will only take a day or two to grow out to the buzz cut length.
Secondly, always remember that you are not your hair. Your hair does not define you. We're all conditioned to thinking that our hair is the single most important part of our appearance, but it's really one part of the total package. Start working on the other parts of the package. Upgrade your wardrobe. Get to the gym and work on getting in shape -- either lose weight or bulk up, whichever you need to do. A good physique more than compensates for a lack of hair. I'd much rather be bald and muscular than hairy and out of shape.
Acknowledge that your appearance is changing, and instead of being afraid of it, embrace it. You're not turning into George Costanza; you're becoming like Vin Diesel, Bruce Willis, and Kelly Slater. Can you imagine Yul Brynner with hair? Look at this before and after photo of Neil Strauss. Which one looks better?

Be glad that you're living in a day and age when it isn't a big deal to shave your head. This wasn't an option 20 or 30 years ago. I wish I'd started shaving my head when I was in my 20s. Being bald is only a big deal if you let it be one. Strange as it may seem, one day you may even grow to like it.