Blaine, don't give up, dude!
Like Lil_G said, you need an intervention. Tell the alums that if they don't get up there and help, THIS IS IT. The fraternity will not be there for them to come back to. You don't want money, you want time and suggestions - you guys have been around for a while - this can't be the first rough patch you've gone through.
Ask if maybe they want to do another philanthropy - or conduct it differently - I know a lot of our sisters got burnt out on doing the same thing year after year.
Try writing down everything you feel, and either reading it at your next meeting or emailing it to everyone. Let them know how close you are to just saying the hell with it. I've never seen you be this upset on here - you've had nothing but pride for your brothers - so I know you must be at the end of your rope to talk about disaffiliating.
Email or pm me if you feel like letting loose a vent, ok?