My sperm donor is driving me nuts 🤦

Okay so, to make a long story short, my sperm donor and I decided that the best way to make conception happen would be natural insemination (essentially, having sex to make a baby, with the same idea as artificial insemination- he will have no involvement with the child.)

Anyways, when him and I have babymaking sex, it is either the best sex of my life or the absolute worst thing I've ever experienced. He can only achieve an orgasm in certain positions and those positions just happen to be the ones I hate the most. I have scoliosis and recurring tendonitis, so being in doggy style for an extended amount of time is fuckin painful, real talk. And in the time it takes me to change positions, he loses his erection.

He's a wonderful person, one of my absolute best friends, and this dynamic hasn't complicated our friendship at all. However, I am a lesbian, so I'm starting to wonder if my dissatisfaction is because of his quirks or because of the fact that I'm not attracted to men.

I surely don't want unwelcome commentary on my decision to let my best friend be my sperm donor. My lawyer, doctor, and therapist are my advice committee for now and I'd respectfully like it to stay that way. However, as to the logistics of the sex-- should we try to just do artificial insemination? Or should we stick it out and try to find a position that works for both of us?