I'm fluid bonded with my gf. She is tested regularly as part of her medical care as she transitions, but before we met she hadn't had sex in 3 yrs w her ex (long story), and they'd always used condoms for birth control previous to that.
I'd been monogamous for 32 years myself. So I knew I was clean. My ex had a gf for a while, but she was tested before they had sex.
Now, I've got this boytoy, my FWB. We've been together 21 months and he's mostly just been with me all that time (which amazes me sometimes, that I can meet the sexual needs of a horny 22 yr old, lol). He had one short fling last summer, but used condoms. And we always use condoms. I am sure we don't physically need to, as I can't get pregnant, but my gf insists I used condoms with anyone I fuck, to sort of mark her as my primary.
I'd never really used condoms before my ex and I separated. Back when I was single in the 70s, I was on bc pills and got lucky, never caught anything. But then I met my ex when I was 19, lived mono for 35 years, and that was that.
Now, I think condoms are actually kind of kinky! lol Maybe I should surprise the boy with a female condom one of these days...