Mauricio Umansky and Emma Slater's PDA Photo 'Disrespectful' to Kyle Richards

Kyle Richards deleting the photo of Mauricio Umansky and his dance partner on "Dancing With the Stars" was intentional ... it directly connects to the photo of Mauricio walking out of an L.A. restaurant holding hands with Emma Slater.

Sources close to the estranged couple tell TMZ ... Kyle isn't buying what Mauricio is selling over the pics ... he says he was holding hands with Emma because he was overtaken with emotion ... when he talked to Emma over sushi about fond memories of getting married to Kyle. The story and the motivation just don't hold water.

As you may know, Kyle removed the pic of Mauricio and Emma supporting them on 'DWTS' from her Instagram feed, and not by accident.

Fact is ... everyone's talking about a rumored relationship between Kyle and Morgan Wade, although the 2 have never confirmed or denied it. There have been no PDA pics of Kyle and Morgan, so the photo of Mauricio and Emma is a new twist .... some folks close to the couple call it " super disrespectful" to Kyle.

Mauricio and Emma's performance on "Dancing with the Stars" Tuesday night came off as pretty sexy, too ... and people online have been sure to point that out.

That said ... the 2 are still living under the same roof and their relationship is "generally amicable," sources say.

In terms of any possible reconciliation, we're told this photo could be a buzzkill. As one source put it, "It's obvious what's up."