Ryan Phillippe posted about his ex on Instagram. Ryan Phillippe shared a throwback photo of him and his ex-wife, Reese Witherspoon. On Monday, the "Shooter" star took to Instagram Stories to share an old photo of him and Witherspoon posing together in matching stripe outfits in the '90s.

When Hollywood A-listers Brad Pitt and Jennifer Aniston were photographed having a sweet reunion at the 26th Screen Actors Guild Awards last month, left and right rumors about the ex-lovers getting back together immediately sparked.

Dating co-workers is a tricky business in general, but when two celebrities date one another, a break-up can be extra brutal if the two work together.

Breaking up is always a difficult thing for couples to face, but once the initial grieving period for an ended relationship is over, it is sometimes possible for exes to remain friendly.