We don't have transmission stats for oral sex, but the chances are very low. Oral hsv2 is uncommon, and your partner is on daily meds, which reduces the chances even more.
Herpes has sites of preference, and that means that hsv1 and hsv2 acts differently in the mouth and genitals. Hsv1 "prefers" the mouth - it's more active in the oral area, as in it present with more outbreaks (if someone has outbreaks), shed more, transmit more. Hsv2 "prefers" the genitals, so it will present with more outbreaks, shed more, transmit more than if it is in the mouth area.
While hsv1 is very common in the genital area, when it does happen, it's not as likely to shed, outbreaks are far less common, and transmission from the genitals is less likely.
Oral hsv2, when it does happen, rarely sheds, rarely causes outbreaks, and very rarely transmits.
Also, I don't know how much research you've done into this, but we do have transmission stats for sex.
Assuming you're male (just based on your username), the chances of you getting hsv2 over the course of a year, assuming you have sex 2-3x a week and avoid sex when she has an outbreak:
no precautions: 4%
using condoms OR meds: 2%
using condoms AND meds: 1%
If she doesn't have an outbreak, and she's on daily meds, I wouldn't worry about oral sex.