May be nyx is misguiding me with this crying spoiler and What now?
Lexi could be crying for a few different reasons. First, if MC breaks up with her because he's into Valeria after the beach event and also confirms it with Valeria earlier in the day when they were training, stating that he'll break up with Lexi and be with her instead. Second, although I'm highly doubtful about this, it could be because MC is leaving for Alvarado. Lastly, it might be due to MC telling Lexi what happened prior to their visit to Dylan's bar, including John's meeting with Ethan and Erynn, who was called in and also assaulted by Ethan before she entered the building. I'm leaning toward the first option.
The image of MC with his head on the bar and Lexi smiling at him could suggest that she is teasing him about thinking he slept with his own sister, when in reality, Santiago is her dad's friend and agent.