Imagine a mother who's lost her child recently. She's vocalizing and singing beautiful and tearjerking love songs to herself all the time, because she loves to reminisce about her lovely departed child. Sometimes the rest of the family join her: she sings and they all cry and sigh and stuff. You might say that she has a nice voice, but that's not the point in what she does. There's no intention of amusement or entertainment or showing off. It's all about remembrance and grief and (subconsciously) taking solace.
What is the term for that?
Edit:
I want a verb that describes what she does.
I know of such verbs in Persian and in Arabic, but couldn't find a good English equivalent for them.