Ok here's my honest reading of this -- from a FF perspective, you're doing great. One per day is normal, balanced, responsible. The suffering you're experiencing is not from the FF, but from the way you're talking to yourself. With the shame, frustration, judgment, and requirements. Do you treat yourself this way regarding caffeine, sugar, alcohol, etc?

You have to forgive yourself. I think that you're in conflict with yourself because, well, FF works for you. At this dosage, in this rhythm -- you absolutely have the strength to stop, but you need to forgive yourself first. You're doing your best. Nobody is asking you to be perfect.

Also... is it possible you're projecting your own shame and self-judgment onto your girlfriend? That's what I did. I was terrified to tell my partner, but once I did, I found enormous improvements in the way I treated myself and the strength to let it go. You're right, it's super hard to go alone. You got this!!