I don't know about the allergy aspect, but alchohol as you probably know is a diuretic. This means that unless you drink enough water with it you can become dehydrated. Also of course it is a sedative. Putting the two together, a night drinking followed by the sleep that follows, without drinking enough water, leads to a reduction of urine in the bladder, and consequently more overnight it becomes more concentrated (many of the symptoms of a 'hangover' are also from dehydration). A bladder with concentrated urine in is a good breeding ground for bacteria, and in addition can irritate the bladder walls and urinary tract, causing cystitis like symptoms. So the answer is yes, alchohol and UTI's can well be linked. The solution is either not to drink, or to ensure that enough water is taken, and eliminated out, before sleeping. I really cannot work out the allergy connection but there may be one. It is more I believe the case of poor bladder hygeine which comes with being inebriated.
If your daughter's bladder problems continue to worsen it will be very useful to have a urodynamic study done. This will show how effectively she is emptying her bladder and if she is prone to retention, which will also make infection more likely. Hope all this makes sense to you!
I do not think Alcohol is the problem.
If the urine cultures are coming back negative, then she does not have the infection, just the symptoms. Cultures need about 3 days to get the results, not the "dipstick" tests that are done in the office.
Get her checked for STD's in the cervix, vagina, and urethra. If these are all negative, then have her see a pelvic floor physical therapist, who can evaluate her for painful trigger points in her pelvic floor muscles. If these are present, the physical therapist can treat her for these and cure the problem.
Dr. Hoyte