The Jaguars are 3-3. If you honestly can only support the Jaguars when they win, perhaps you should buy a XBox 360 or a PS3 and buy Madden. This way you can ensure your team always wins.
The Jaguars won't always win and they won't always lose. And yes they look like crap when they lose recently but when your head coach and starting QB pretty much know next year they're not going to be there it leads to an unmotivated team and players who aren't going to give it their all when the chips are down
As of right now we have 4 home games left against some uninspiring opponents. At the very least, if you have no pride in the Jaguars, have some pride in your city. Show up at home games, and if you don't live in Jax but are a fan, go see them on the road. Because you show up, and people will stop trashing your city. Of course you could always go the Raiders route and have your games so empty no one even talks about it because they've been doing it for 20 years.