"After considerable thought, much reflection and mixed emotions, I am sorry to announce that several months ago, Brenda and I decided to separate," DDP announced ... "and after a three month separation we have filed for divorce."

Dallas and Brenda have been together for years -- and tied the knot in a lavish ceremony in Cancun, Mexico in 2015.

Page famously proposed to Brenda at her 50th birthday party -- the video was awesome.

As for why they split, DDP explains ... "While we both love each other, we recognize that we are two strong-willed people who will be happier if we part."

"As painful as divorce is, we are thankful that no infidelity or other love interests were involved in our decision and we are parting as friends."

"I want to thank all of you in advance for your support as we move into the next phase of our lives and I ask that you respect our privacy and keep us in your thoughts and prayers."

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