He forced his head up, his red, puffy, bloodshot eyes looking right into Sweetie's, "I knew if you got famous that you would be that pony for them, and you have been.  For six years you've made thousands of young fillies and colts feel good about who they are while reminding them that they're all special.  If you would have stayed in Ponyville, that never would have happened."  He let his head sink back down to rest on his hooves as his eyes lost focus again.  "If you would've stayed, every day you were here, and every time I saw a little filly crying because she didn't have her cutie mark, I would have known that you could have been out there, inspiring fillies and colts just like her to be proud of themselves and to stay positive.  That would have killed me.  Knowing that I was keeping you here, and that I was the reason all of those little fillies and colts didn't have that pony in their life telling them that they were special when nopony else seemed to care.  Can you understand that?  Even with you by my side, that would have ate at me until I was nothing more than the shell of the pony you fell in love with.  Nothing but a dead husk of a pony so ashamed of his own selfishness that he was basically dead on the inside."