Kim, maybe it is how you are working out. I know everyone is different but for me High Intensity Interval Training 3 days a week seems to bring the best results. I have tried the 7 days a week for an hour or more, I have tried the 5 days a week for 45 minutes, I have tried various combinations of those but the only time that I seem to be able to keep my metabolism working for me is when I do Interval training 30 sec. of hard (heart rate 180 work) followed by 90 sec. of really low interval getting my heart rate back under 140. I also walk and do WII fit but I don't push it on either of these. I do the HIIT Monday, Wed, and Fri and try to go for a leisurely walk daily and do some WII fit just because it is so fun, for about 1/2 hour a day but I do things like Yoga and Balance games more than the Aerobics part of it on my off days.
Sundays I give my body a complete break from everything. I don't know if any of this will work for you but hopefully it will give you some change up ideas to see what will work best for you.