Dwyane Wade & Gabrielle Union -- Evidence They Were NOT on Break When Baby Was Conceived

Exactly 9 months before Dwyane Wade's son was born (by a woman who's NOT his fiancee) ... Wade and Gabrielle Union were still acting like they were very much a couple ... and TMZ has the proof.

We broke the story ... Wade's baby mama Aja Metoyer gave birth to Dwyane's son Xavier on Nov. 10. Wade claims the two were on a "break" at the time.

But on February 5th (9 months before the birth), Gabrielle was Instagramming about Wade ... posting a photo of the NBA star cuddled up with her dog Sasha along with caption, "Sasha don't play when it comes to her man... 'Down to ride 'til the very end, it's me and my boyfriend.'"

A couple of days before that (on Feb. 1), Gabrielle posted a romantic photo of the couple together from a photo shoot for a "Flashback Friday."

Doesn't seem like a couple on a break ...

There's more ... on February 19th, Gabby posted another pic of Dwyane holding one of her scripts ... with the caption, "It takes a village to help an actress learn her lines... @dwyanewade takin a break from his Gatorade commercial to give me a line reading. Thanks coach :)"

The patter continues until April ... when Gabby stopped posting pics of Dwyane and started posting a bunch of sad cryptic quotes. One reads, "We cannot start over, but we can begin now, and make a new ending."

Another says, "Sometimes you have to get knocked down lower than you have ever been, to stand up taller than you ever were."

But on May 16, Wade returns to the picture ... with Union posting a photo of the couple, along with the caption, "I like this dude."