Tristan Thompson & Khloe Kardashian Not Back Together

Khloe Kardashian and Tristan Thompson aren't together again ... even though they've been in each other's company a lot lately.

Despite recent reports that have surfaced claiming the exes are back on again -- and that Khloe is "desperate" to make it work, despite repeated instances of cheating -- sources that are actually plugged into the situation tell TMZ ... all of that is a load of baloney.

We're told Khloe and Tristan are not romantically linked whatsoever ... regardless of recent pics of them side by side with True. Just last week, they took their daughter to a movie, and exited together ... looking like a happy fam.

It's not the first time they've been photographed in close proximity since the split -- remember, they both attended True's dance class earlier this year -- and we're told it won't be the last time either ... as they're committed to presenting a united front for True's sake.

Our sources say Mom and Dad are fully aligned as parents, and want True to see her parents maintaining a healthy relationship -- which apparently means semi-frequent joint outings.