Mood stops me playing

Hi folks. I have been reading here about the severe pain some of you have to deal with day after day. My hand problem is minor in comparison. But what does affect my playing pretty regularly is a down period in my mood. I have bipolar disorder and my meds stop it from being extreme but I am left with regular bouts of what I call 'athe very low fug'. I know we all have off days but mine are a bit more 'off' than many peoples and I got to thinking that folks on here living with pain might go through similar periods. What annoys me about mine is that they stop me playing my dulcimer. I know music can be very healing but when my 'fug' is bad the happiness of the dulcimers tone just makes me more conscious of how low I am. Sometimes I can manage a soft version of 'Sweet Chariot'. Can anyone suggest similar tunes or particular mellow tunings that I might be able to play on these days. I am due to receive a bass dulcimer from Dave Lynch soon. I am hoping it might suit these days.