I have been working with tonglen and metta bhavana for the past week or so and have noticed that i have been experiencing what might best be called compassion fatigue over the last two days. I have become pretty familiar with the feeling of a dry, unworkable heart so when i became aware that this was happening with the tonglen practice i switched to metta and proceeded through the rounds until i came to a point where the heart felt supple enough to give it another go.
Unsurprisingly the feeling of hardness and constriction returned rather quickly but it suddenly occurred to me that the absence of suitable subjects for compassion simultaneously meant that i had a wealth of people in my mind for whom i could cultivate mudita. And, even though the mind was tiring as i approached the forty minute mark, the fact is that sourcing to sympathetic joy worked amazingly well to brighten the mind and open the heart.
It appears to me that the morei practice, the more willing i must be to listen to the heart and to experiment in order to discover the appropriate response to each moment. May your good fortune not come to an end!