Yo duder, how's it going?
I can empathise with what you're going through. Hell, I broke up with my lady about 3 weeks ago myself. You're probably feeling like crap, and me saying something might not necessarily help, but I've always found positivity to help. So, without further ado:
May I point out that you're probably already an interesting, nice, cool person? You've managed to show that you can attract other, interesting people to you, and that if nothing else is a sign that you're awesome! It's hard, but think about all of the good things about yourself. Allow yourself a bit of pride and confidence, maybe even a little arrogance (but just a little) and think about why people consider you as a great person and why you should think so as well. Believe me, it helps put a pretty good spin on life.
And all of the suggestions by @kcin are correct and appropriate. Do something unusual. Do something to better yourself. Learn something new (you could learn guitar, like me! Just mind the sore fingers.) And spend some time with family, friends, and regain that confidence. It all helps bit by bit.
Finally, a really good video that can help is this one by Sean "Day" Plott about positivity:
Stay happy, duder! Feel free to send PMs to anyone here, or someone closer if you'd prefer.