I'm sorry I missed this question earlier.
We don't have transmission stats for same sex couples, unfortunately. We do know, generally speaking, that men who have sex with men have higher STD rates than men who have sex with women. This is because the act of anal sex is more likely to tear the tissues of the anus and rectum than the act of vaginal sex, which provides lubrication.
I can give you the transmission rates for men to women, and you can use those, and assume they're at least a bit higher.
The transmission rates for hsv2, male to female, over the course of a year, assuming sex 2-3 times a week:
Only avoiding sex during an outbreak - 8-10%
Adding condoms OR daily suppression - 4-5%
Adding condoms AND daily suppression - 2-3%
Also, just because you have outbreaks anally doesn't mean you aren't infectious from other genital areas. Herpes infects nerve groups, and genital herpes infects the sacral ganglia. This means that you can get outbreaks from anywhere in the area that boxer shorts cover, and you shed the virus from all the mucus membrane skin in that area (anus, penis, etc.).
You can read more about this in the Herpes Handbook, which is written by Terri Warren, who is one of the world's leading experts. You can find it here - https://westoverheights.com/herpes/the-updated-herpes-handbook/ It's free. :)
Let me know what questions you have, and again, I'm sorry for missing your question earlier. It got lost in some spam.