see: https://www.faa.gov/about/office_org/headquarters_offices/avs/offices/aam/ame/guide/media/DUIDWI_Alcohol_Incidents_Disposition_Table.pdf
you fall under B
and your personal statement...
the bi-polar will be looked at. If it is present, it will be a game stopper. Otherwise this looks like a routine HIMS case, though borderline can be problematic too.
you will share all details of anxiety with your AME. once your application is completed it will likely be deferred the the faa to decide. there is a path to allow you to take lexapro. it takes time and some money to follow it. find an ame you are comfortable with and ask for a pre-exam...
these types of drugs are being added very frequently now. The best way to know your situation would be to to discuss such with the prescribing MD. Good luck.