If you’re brain’s working against you, stop thinking and just MOVE. When I used to have trouble getting going, I would invite friends over to do a new DVD for extra motivation. There are more free workout options than you can even imagine out there: and many are follow along style. Try new things, get moving and don’t worry about the weather!
You don’t need much room to get moving at home: if you can lie down and do a snow angel (fan your arms & legs out) you have enough room to workout. No equipment necessary, just a drive to get moving! Commit to just 5-10 minutes and see how you feel!