Jennifer Garner is looking back on a rough time in her life ... making some rare comments about her divorce from ex-husband Ben Affleck.

In an interview with Marie Claire published Wednesday, Jennifer revealed she did her best to steer clear of all the coverage of her 2015 divorce with Ben, which was all over the news.

Jennifer says ... "You have to be smart about what you can and can't handle, and I could not handle what was out there."

But she said the headlines and stories weren't what was truly hard ... instead, it was the actual divorce.

Jennifer told the outlet ... "The actual breaking up of a family is what was hard. Losing a true partnership and friendship is what was hard."

As you know ... Ben and Jennifer were married for a decade until they pulled the plug in 2015 with a divorce that dragged on for about 3 years.

The exes have been on great terms for a while now and share three kids together ... Violet, Fin, and Samuel.