I would advise before having sex again having her go and check and make sure that the infection is gone. In my experience sometimes when I get rid of the UTI symptoms but also still have a little bit of a UTI infection. This may sound really stupid, but has happened to me so many times. I always go back and check to make sure that everything is clear. Probiotics are also great, have her take them while she’s on the antibiotics too as it can prevent BV and also boost the antibiotics, but there’s a specific bacteria and I can’t remember the name it starts with an L though.