Do you know if your partner has hsv1 already? The vast majority of people who have it never get symptoms. If he has it, he has antibodies that protect him from getting it again.
Have you considered going on suppressive therapy? That's taking Valtrex daily. You can take 500 mgs or 1000 mgs. I'd start at 500, and if that doesn't work, try 1000.
Also, I'd talk to your doctor to find out if something is happening with your body that is triggering all these outbreaks.
You can transmit hsv1 without having any symptoms, though it's more likely to transmit with symptoms. Since your outbreaks are so frequent, I'd consider yourself pretty contagious right now.
There's something called viral shedding. This is when the virus is active on the skin but we have no symptoms. Everyone sheds at different rates, but very generally speaking, the more frequent the outbreaks, the higher the rate of shedding. (This isn't always true - some people who never get outbreaks shed frequently, but for now, to be on the safe side, let's assume it's true for you.)
Your partner can get a type specific IgG blood test and find out of he has herpes. The hsv1 blood test isn't great - it misses a full 30% of infections. But if it's positive, at least you can relax, right?
He can get a test from his doctor, or if you're in the US, he can go to STDCheck.com or HealthLabs.com and get the test -
https://www.stdcheck.com/herpes-1-test.php
https://www.healthlabs.com/herpes-tests
He can order just the hsv1 test separately on both of these sites. He doesn't need to pay for the hsv2 test, and if he does get the hsv2 test, please note that there are false positives on those.
So, is it possible you transmitted this to him days before? Yes. It's not as likely without a sore, and you need to find out if he has it already. 67% of people under 50 have it globally, so he might already have it.