I've recently seen some statistics about perceived happiness by age distribution. Turns out, it's sort of an inverted bell curve. People in your age group are feeling significantly worse off because the more positive youth experiences are still quite fresh while you're not ready yet to adequately deal with the downsides of adulthood. This is a kind of midlife crisis. The good news is: It will get better, statistically.

And a more personal note from someone suffering from intermediate depressed states: It might not really help you right now, but there is a soothing realization in that most of the burden you are feeling right now is only in your head. A different state of mind is possible, but you'll have to work on it. The big foggy cloud surrounding your head is not THE reality but your current perception of reality and that can be changed. Sometimes it helps to just get a different perspective, and you'll get to that if you try new things that look even mildly interesting. Get out of your so-called comfort zone (which isn't that comfortable anyway as you know by now) and do little things every day that you haven't done before. Even if the specific things you are trying out might turn out to be a failure, you'll discover other interesting things along the way. A word of warning... Don't let anyone guilt trip you, if you try new things. Your environment usually doesn't want you to change and that can be a problem, because if you change yourself your environment has to deal with that change too. So make sure you find people who support you as a human being, instead of just supporting your role as a good parent, employee or debtor. Also check for yourself if all the things you feel obligated to do have to be done in the exact way you are doing them right now. Maybe there are some adjustments to be made to gain more personal freedom, to get regular breaks from the chore in your daily life.

Good Luck!