Teddi Mellencamp says she's getting a divorce ... splitting with her husband of more than a decade, Edwin Arroyave -- adding she's speaking out to stop any unfounded rumors.

The reality television star announced the news in a post to her Instagram ... saying she came to the decision to file after a great deal of consideration.

She goes on to say her kids are her priority ... and, she will take every step to ensure their care and privacy during the split.

Mellencamp goes on to say she didn't plan on making a public statement ... but, she acknowledges she feels it's necessary to stop anyone from spreading rumors about her fam.

FWIW ... Teddi doesn't actually provide a reason for the split or even say anything directly about Edwin in the post -- so, we have a feeling rumors are going to take off anyway.

Teddie and Edwin met way back in 2008 ... hooking up in what Teddi initially thought would be a one-and-done fling.

Three years later, the two married ... though Teddi did admit she thought about divorcing him during their first season on "The Real Housewives of Beverly Hills" in 2017 -- saying they were "at our worst absolute phase, because truthfully, for us, it was really about a power struggle."

The couple shares three kids: Isabella, Cruz and Slate.