I was once like that, but -with the risk of sounding like a crap fan- don't you think you sort of grow out of that somehow? I did anyway. Let's say that I was down for days when my team lost back when I was a young teenager. Then my psychological problems hit me really hard during my mid-teens and I realised that "it was only football, only a game". I was happy just to attend games and be distracted from my real issues for a few hours, to have a break from daily issues. But shortly after the game those real problems are there again, and then you sort of realise that a defeat or a relegation in football is just a bad result but nothing more. It is a game. In the end the real issues in life are your job, guaranteeing an income, support your family (if you have one), ... Football is a pleasant hobby but I have difficulties in taking it too serious. I wouldn't want to anyway, not even the worst defeat comes anywhere near the seriousness of real problems: finances, health, unemployment, you get what I mean. I am happy I have football and groundhopping on weekly basis to offer me amusement and a break from those serious issues, but just being at the stadium and enjoying myself is fulfilling my needs really, the result of the game is nowhere near the priority.
Maybe I am no "die hard" then but I can easily smile again 5 minutes after losing 9-0, or sleap well after my team has just been relegated. Some really difficult times during my youth have put football in perspective to me, and having a game without worries to me is actually my own victory even if my team is losing heavily. I still need Xanax with me as a panic attack can occur at any time even during a football game, to spend an entire day out (leaving for an away game in the morning, seeing the game without any hassle, and returning home in a good mood) without those issues is my own victory even if my team just lost quite badly.