“Vanderpump Rules” alum Jax Taylor was spotted out in May with his estranged wife Brittany Cartwright‘s longtime publicist Lori Krebs … months before their cozy Mexico pool pics surfaced … TMZ has learned.

TMZ obtained a photo of the duo at a Flanigan’s Seafood Bar and Grill in Boca Raton on May 15 … about two months before they were spotted in the pool at a Mexican resort.

Folks who were there tell us Jax and Lori were very low-key and drinking soda as they bellied up to the bar on a Friday night.

We’re also told the pair seemingly did not want to be recognized.

However, due to newly surfaced photos we obtained of Jax and Lori getting quite cozy in a pool in Mexico last week … it makes you wonder if the trip in May was really for business, or for … well, you know.

Jax and Lori are seen embracing in the resort pool, standing chest to chest while talking and, at one point, wrapping their arms around each other as they floated together.

A witness told us the PDA went even further than what our cameras captured … claiming Jax and Lori were getting close and hugging throughout the day and weren’t trying to hide they were together.

We’re told Jax and Lori were in Puerto Vallarta with a larger group of friends, celebrating Jax’s birthday — which was on July 11.

As we previously reported … sources with direct knowledge told us once these images and video went live, Brittany decided to cut ties with Lori on Monday.

We’re told Lori had called Brittany before TMZ published the photos to give her a heads up that the story was coming … but the two haven’t spoken since. Our sources say it’s unclear whether or not Jax reached out to do the same, but that they wouldn’t be shocked if he forgot to press send.