Does your boyfriend wear a hat, talk really loud or have a skin or hair color Bowie is unfamiliar with?
He keeps hurting family members.
You're giving me mixed signals here, haha!
Is he aggressive to
only him or just anyone who isn't you? Is he fine with your mom, your friends, etc?
If not, he's probably overbonded. Seems like a common problem with conures. If it's a
really big issue in your home, I'd tentatively suggest trimming Bowie's wings. My extremely overbonded conure used to be a monster but now he'll contentedly sit on his stand when he used to fly and attack family members. I'm hoping that by the time they grow back in, he'll have learned to behave himself around my family.
If Bowie's wings are already clipped, I can't offer you much advice besides the obvious; Don't let him near Boyfriend. Or better yet, put him in the cage when lover-boy rolls around. Preventing bites is as simple as preventing the situations where they occur.
And if Bowie
only has a quarrel with your beau
and no-one else, the problem is essentially the same. There may be a small chance of changing Bowie's mind by having Boyfriend deliver treats and whatnot, but if that doesn't work, don't push it. Birds pick their people. If I were you I would accept his decision and allow him to hate Boyfriend as long as he can control his aggressive urges and behave when he is in the same room as him.