Zac Affleck is speaking out about his estranged wife Jen filing for divorce … and says this was on the horizon for a while.

“The Secret Wives of Mormon Wives” star addresses the split in a video he shared on social media … saying that, while the filing was news to him, his wife wanting a divorce was not.

Zac says he knew Jen’s wanted out for a year, saying she came to him after “Dancing with the Stars” and made her feelings known.

The way Zac tells it, he begged Jen to stay and told her he was willing to be whoever she wanted … but ultimately they still couldn’t make it work.

He says he still has love for Jen and will always support her, but his priority right now is to figure out how they move forward with their kids. They have three children and a fourth on the way.