Does anyone else ever feel depressed in spite of having a good life?

[cloud1161]

Right now I am just feeling like a complete loser.  I got e-mail from a company called NetApp saying I didn't get the internship I interviewed for and ever since just felt like my life has been a waste.  I have been turned down positions in the past, but this was one I really wanted and I thought I did alright in the interview. Now I am just going through my thoughts thinking of how unordinary my life has been.  I like to think of myself as an optmistic person, but for some reason I just can't get out of this slump.  I was just thinking I can't remember the last time I had honest care free fun.  Isn't that a little sad for a 21 year old?  Sure I hang out with my friends and I have a girlfriend, but I feel like my is going to be over before I ever get a chance to enjoy it.  

 

EDIT:  I just want to thank everyone for their kind words.  I am feeling much better today and it is in part due to you guys.  This was the first time since I started dating my girlfriend, which will be 3 years in January, that I felt really down.  I hope it doesn't happen again for another three years.