aggression or just overly nervous
 

Priscilla used to be so friendly and was a joy to take out in public until a few months ago when my mentally handicapped cousins were over and kept touching her when she didn't want to be touched. Ever since then she growls when someone except for my immediate family tries to pet her. She is fine and is so happy when out in public until people put their hands in her face or on her. When people asked to pet her i tell them no because she is shy and gets frightened easily and I don't want to risk her biting them. Sometimes people just reach to pet her without asking and she growls. She has never bitten anyone before and I don't think she ever would unless provoked to the extreme. How can I get Priscilla to calm down and let strangers pet her on her back, so hates for me to pet her head/face so I don't think she would ever allow strangers to touch her here. I don't think she is aggressive I just think she is so nervous around others. She is fine until someone gets to close and then she starts to shake and growl.

Aggressive dogs will usually initiate barking, growling, showing teeth to get people/dogs to move away because they are fearful or unsure of them. Sounds like she was upset by that experience of the family members, felt as if she had no control of what was happening and it made her unsure around people she doesn't know. Inviting people into your home one at a time to slowly desensitize her to people could help. Have the person come in, don't look at her, talk to or touch her, sit and visit with you while totally ignoring her and then leaving in 5 minutes or so could start to get her used to strangers being around and teach her there is no harm in them. After three or four have done this visiting-while-ignoring visit with you daily for two weeks, have each person now start to toss out treats on the floor near them from time to time for her though still strictly ignoring her. After another couple of weeks of that, a visitor could see if she will start to act friendly, approach or sniff by placing a hand down by the side of a chair, maybe with a treat in it. Allow them to briefly interact with her if she does approach but leave fairly quickly after she initiates their attention and to leave her wanting more. In time, with more visitors and time, she should regain her enjoyment of having people visit and interact with her.

She probably is fearful after having such a bad experience. It is really important to never let kids or anyone else handle our pets without our direct supervision. A lot of damage can be done by kids or others that have no sensitivity to an animal's feelings.

It is going to take some special handling to get her trust level up to what it should be. Yorkietalkjilly's suggestions are sound. Take it slow and don't let just anyone work with you with this situation.

I mentioned in my original post that my cousins are mentally handicapped. I don't think they really know any better. I wasn't home, or it wouldn't have happened. One of my cousins came over this morning and I told him to ignore her until she stopped barking them to just let her smell him. After about 10 minutes she finally calmed down and jumped into my lap and just sat there. I take that as a good sign because she didn't shake or growl. She sat calmly and even jumped down to get a toy like she wanted to play. I wasn't sure if this would have been to much to start with so I took her to the park for a walk until he left.

Thanks for giving me your opinions! :)