First thing, I love workouts. I also do some cardiac exercises but I love weight training. Second thing, I like to meditate for few minutes. I think this is really really good for mind. I feel very relaxed when I meditate.
Workouts definitely helps...and some fresh air...I felt a lot better after went out watch fireworks with my daughter last night, even though it took us 2 hours to get back home
Fresh air and working out definitely helps - a combination of the two is even better! A walk to somewhere you'd normally drive is a great way to have some peaceful time to relax (weather permitting!)