Hi and Welcome to you both, Bud and Su.
Why would you think you are abusing your beautiful lady? You might be abusing her if she didn't enjoy it and you thrust her into this wild world of swinging without her full consent, or, maybe if you were expecting her to go faster than she is comfortable with. Do you think you might be abusing your relationship? You're taking her for granted? Hopefully, you both go home together and make mad passionate love after you've played?
It reads to me that maybe you weren't ready for it. She is maybe going faster than what you're comfortable with?
I think if I were you Bud, I'd be sitting Su down and have a talk with her about YOUR feelings. What you're not comfortable seeing her do, what you're not ready for and what you'd like to see happen the next time -- if there is a next time.
As far as the OP goes, I'd like to hear more about his situation, and I like the others, would like to read his explanation.