I'd call it "me time".

#Me time

[MASS NOUN] informal

Time spent relaxing on one’s own as opposed to working or doing things for others, seen as an opportunity to reduce stress or restore energy

"schedule some me time when you get home"

Me time — ODO

mass noun, informal
Time spent relaxing on one’s own as opposed to working or doing things for others, seen as an opportunity to reduce stress or restore energy

"schedule some me time when you get home"