He's taken on the purple dragons, countless kraang droids, the Foot, even the shredder himself but to Donatello all the pain he went through those battles were NOTHING compared to the pain he's in right now. But who can blame him? After 5 years of trying to show someone you love them, how else would you react when they bounce into the Lair with a diamond ring on her finger? with a broken heart, no doubt.