It's been a while since I felt intensely sad. It was an exquisitely beautiful experience. I was grieving over the suicide of a friend.
I very much enjoyed the feeling of sadness, it was transporting, transforming, and very relaxing. At times my breath slowed to almost seeming to stop, music became profound, infinity seemed to pour in from some kind of absolute stillness.
I reveled in it and concentrated often to linger in the emotion as much as I could.
Alas, I cannot conjure up these states at will , they have a life of their own, eventually my long term sadness passed.

That seems to be the general rule ,ie the more one accepts and loves one's negative emotions the less likely they are to stay and the more one runs form them the more power they get. But 'mother psychology' cannot be tricked, if she senses you are trying to enjoy the emotions to make them go away then she she will bring them back in force. 'Mother psychology' always demands absolute honesty.

To my understanding, there is the emotion which is inside me and part of me, as I have accepted these emotions I love their expression and there is the external event the loss of a friend which is outside of me and the pain is my consciousness of it. So perhaps the sadness is the buffer between, a soothing of the external destructive event to the internal of me.
In any case the emotions, and this emotion is me, it is myself and as I love and accept myself ( an ongoing process which has been progressive) I love all my emotions without reservation. It takes a while though to learn this, and not everyone want to do so. But the choice to progress towards acceptance is always there.