Your attitude is not unusual, Chickster. There are a lot of "soft-swing" couples who feel as you do. It is, indeed, a valid viewpoint in swinging. Some couples kiss, pet, perform and receive oral sex, just about everything short of inserting a penis into a vagina. Others do everything but kiss. It's a personal choice that each couple must make. Of course, your playmates need to agree with you.
Swinging is filled with compromises and perhaps that's the answer for the two of you. While Mrs. Alura and I agree with your husband, that "sex" and "making love" can have nothing to do with each other, it is necessary that y'all proceed at the pace of the slowest partner.
Besides, if he were to agree to your limitations, and find a "soft-swing" couple to play with, he might find in the future that you might throw your limitations right out the window after you become comfortable with the lifestyle and the couple y'all choose to play with. It's happened before...
Mr. Alura