Yes, the supplemental test being negative means that you don't have hsv2.
A 1.73 probably is higher than a 50/50 chance of being negative - the 50/50 is anything below a 3.5. The lower the number, the higher the chance it's a false positive.
Given that your partner is negative, you were negative at the start of your relationship, that you're a lesbian (women who have sex with women have lower rates of STDs overall, just given the nature of sexual activities), and that you'd never had PIV sex, I'd have been very surprised if you had hsv2.
I'm sorry you've gone through this, but you can relax now.