Join RVing Women, a support group for women like you. The group publishes a newsletter and has regular gatherings. The address is P.O. Box 1940, Apache Junction, AZ 85217. Many single or widowed women travel in RVs these days, some alone or with a companion. It's common and popular.
Most campgrounds allow pets.
Some private ones will charge a dollar or so extra. Most have strict leash laws. My wife is in a wheelchair. Check with Poulsbo RV, where they generally have information on ordering a vehicle especially designed for the disabled person's needs. RVs are also great ways to travel for parents with disabled children who might not be able to conveniently travel otherwise.