Congratulations on the hard work you did nursing your baby for 11 months. Good mama!
For some women making the transition from "breasts for nourishment" to "breasts for sex" is difficult. I am a Board Certified Lactation Consultant and not only get this question a lot, but have worked with the opposite problem: women who ONLY see the breast as sexual and refuse to let the child nurse. Sad indeed. Your issue is not as difficult to deal with as you once saw your breasts as sexual, still breastfed your babies and now embracing the dual role of the breast will be easier.
Think of the breast as "double duty glands." Something can be sexual AND utilitarian at the same time. Your vagina helped birth your baby, yet is still used for sex. Your mouth is used for eating food and breathing, and still used for sex. The breast, likewise, was used to nourish your baby and still can be happily used for sex. I always take it slow when I have nursed a child, and ease into full breast play. Eventually, you will remember how much fun breast play is and the duality of your breasts will become part of your every day life.
As for "sagging" I can assure you we know scientifically that breastfeeding does not cause sagging. Pregnancy, heredity and age cause sagging, breastfeeding does not. A woman who has been pregnant but NOT breastfed and has a genetic predisposition to sagging will sag just as quickly and just as much as a women with the same genetic condition who did breastfeed.
Feed your babies as long as you both enjoy it. Breastfeeding not only protects you from breast cancer (up to 80% reduction, if done long enough) reduction in ovarian cancer, uterine cancer etc, but also gives your child immunities to many illnesses and cancers all the way into his or her adulthood. And baby girls who are breastfed have a much lower risk of breast cancer themselves.
