Courtney Love reunited with her daughter Frances Bean Cobain ... apparently closing the book on a feud that's been raging for years.

Love and Bean hugged it out Saturday at the Sundance premiere of "Kurt Cobain: Montage of Heck" ... the first time they've been seen together in more than 5 years.

Remember, Courtney lost legal control over then 17 year-old Frances in 2009.  In 2012, Love accused ex Nirvana drummer Dave Grohl of hitting on Bean.  

The 22 year-old blasted her mom over the allegation ... urging Twitter to ban her mom from the site.

Nothing is forever ... and that can be a good thing.