There are several reason to exercise, one of which being the obvious. Many others are just now coming into the spot light of the public eye. Exercise prompts the body to release certain hormones that just makes one happy. You might want to give it a try. Of course bare in mind the standard, don't start something too strenous, always consult a professional yadda yadda yadda.. just be smart about it.
This will help with a lot of the issues that you mentioned. I'm sure I don't need to, but just incase. Please keep in mind that exercise burns calories. If you are not eating healthy or often, most reccomend gazing 6 times a day, then you will just wear yourself out. Not good.
The traditional 3 meals a day is a MINIMUM. Most people miss this part of their nutrion class.
Good Luck, try it out for a couple weeks, and let me know what happens.