Not all BO and sweat are made alike, and if the sweat isn't fresh (and, for example, dries on clothes that aren't removed or, worse, reworn), it can smell sour. But good BO can be so good. Your girlfriend is hardly alone. In fact, there's a gay party in New York called Pheromone that caters to guys who want to stick their noses in each other's pits.
My partner and I are both in our fifties. I was divorced and never had kids, while my partner was a single mom of three for most of her life. It has been an adjustment coming to live together and learning to navigate each other's space. The one place I am not willing to compromise is the privacy of our bedroom. It is an adult space for adults, but her grandchildren have zero respect for that fact, and the situation is getting very uncomfortable.
He lives with his openly gay male best friend of about 10 years, which is pretty impressive given that we're both in our early 20s. I guess he and his best friend trauma-bonded during high school, and it's made them close. REALLY close. Whenever we go on dates, he keeps his phone on alert to make sure nothing bad happens to his best friend.
Different couples make all kinds of different pacts with each other some spoken, some unspoken. In your partnership it seems you originally found parity; you both benefited from the arrangement between you. Aside from being happy in your everyday lives together, you were able to use your sexual creativity to satisfy him, and in turn perhaps he was able to avoid having to acknowledge aspects of his sexual orientation that made him uncomfortable.
Butch is a rescue who has some trauma from his earlier life. He's shy and timid and doesn't like children or vacuum cleaners. I lived with Butch for almost three years; my own dog also lived with us during that time. Last year, while our house was being vacuumed by a housekeeper, Butch bit her on her calf. I was there, and I attended to the woman and made sure she was OK.
I've been honest with him since the start of our relationship that I'm not interested in being a parent. I find kids really emotionally draining to deal with because they require so much attention and maintenance. Maybe I should never have started dating him because of this, but if it weren't for his daughter he'd be the complete package. I'm OK at dealing with the kid; she likes me and I've babysat a few times, as have my roommates.