In the second video of your linked post Nick says when he was lowest Kayla was there for him & was at her highest. Then he says whatever jargon about them still learning & growing together, already forgot, but along those lines.
Instead of bickering who cheated or started the degeneracy perhaps this thread should ponder if Nick meant the word “highest” in a literal sense & if the learning & growing together they’ve done was more like addicts bonding.
In any case, Nick’s jaw movements indicate he’s definitely on something (drugs in addition to alcohol) & his addiction is worse than ever before.