Why did it happen?

I still can't understand why Waverly's kiss with Rosita happened.

Some say that it was impulsive, others say it was completely driven by lust.

Thing is, Waverly did show some signs of being attracted to Rosita. She said, "hottie mixologist" in 2x05, and even called her, "Rosie." And when Rosita called Waverly, "Waves", Nicole appeared slightly jealous. And Waverly did appear a little flustered when she got into the hot tub. Just like how she appeared flustered when in front of Nicole in 1x02.

And while Emily Andras said, "Both girls were drunk, emotional, and in a hot tub," they seemed like flimsy excuses to me. And Waverly hardly looked drunk at all.

And the fact that it happened right after sending Nicole that awful text makes me wonder whether or not Waverly was truly acting impulsively. Waverly sends Nicole a bad text, regrets it, then kisses Rosita quickly afterward? It makes no sense why she'd do one immediately regrettable act so soon after another.

And while Waverly looked sad about the text, when Rosita began talking, Waverly smiled a bit at her words.

I noticed that right before the kiss happened, Waverly did appear to have a look of lust. And the kiss wasn't a small, quick peck. It lasted for a few seconds before Waverly pulled away. That makes me feel doubts as to whether it was really impulsive. And even towards the end of the episode, Waverly still seemed to stare at Rosita, "like a midway attraction. I always wonder what would've happened if they were both single when the kiss happened.

I also noticed how Waverly seemed to be attracted to Beth as well. Like how Beth called her lovely, and Waverly smiled at those words. I worry about what would've happened if Nicole hadn't walked in just then.

But yet, when Waverly pulled away from the kiss, she seemed to genuinely look surprised. As if she wasn't 100% aware of what she was doing, so I'm not entirely convinced that it was completely driven by lust.