M.R.
First you have to protect you child becaue she needs special treatment to keep her from being hurt. That is fair for your daughter.
If your daughter does not want to play with this girl, she shouldn't, and if this is an inappropriate friend for her because of her special condition, you should keep her away. Cut the ties, and tell the parents that you are doing it because their child is too impulsive and has a history of not controling her behavior. Be honest about why you are doing this. But don't straddle the road or add all this other garbage. It makes you look petty.
You know that you are wrong and that is why you feel guilty. Every child with autism is not going to have the best set of parents there is. Fact of life. You have no idea how well equiped they were to handle the microscope you put them under either. You are seeing what so many people see when they look at our kids. They see children who look just like other children sometimes, but then have a problem and assume that they should always look like other kids. Your child looks like other kids all the time too, untill she breaks a bone, so is that your fault for keeping her bones unbroken MOST of the time, that she does not appear to have this condition such that another parent may question YOU that your child has an issue? Put that shoe on right now, and think about how uncomfortable it feels. The fact is, most parents with kids on the spectrum have worked harder than you had to to get our kids to look like yours most of the time. It is really hurtful when you, and everyone else, says that we did nothing right when they just happen to fall back into looking like they looked when we got started working with them. That is the reality of it, like it or not, blame us for what inconvieneces you it makes you feel better, but imagine what that kid would act like if her parents had never done anything to help her. But wait! If that kids parents had never done anything to help her, she would not be in class with your child, and when you saw her rocking in the corner of the cafeteria with the MRDD kids, you would think how horrible her parents were that they did not do something to help her more...which one sounds better to you? Listen, the last thing you want too, when your child breaks a bone is to see a little group of Moms in the corner of the play ground, looking over at you and giving you that look that says, "she knew her kid would break her arm, why did she not keep her safe?" Isn't that right? We are no different.
You are way off base about the autistic child leaving the room. She gets to leave the room so that she does not have an autistc outburst and disturb your child, just like your child gets to avoid things that may break her bones. Do you let your child climb the rope in gym class? Is it fair that a child with bad eyesight gets to wear glasses? The parents may have been asking for all kinds of theraputic, data proven interventions from the school, and what they got instead was a provision that the child could go be alone to have a melt down, instead of therapy to help her prevent them in the first place. So common for schools to just wisk the problem out of sight and call it good. How would you feel if that were the answer for your child?
Come on! I know that you are angry that you are in this situation, and that you have a hard choice to make here, so stop adding up all these excuses to find that you are justified in making a good choice for your child that may hurt another one by finding that this child and her parents are terrible. If you don't like Mom, and you don't like the younger child, fine, but that is not some big, convoluted reason to not just say what you need to. Children with Autism have impulsivity issues, some have anger issues, some have out bursts where they are not in control of thier physical actions (by reason of medical, REAL, nuerological issues) and you have a child who is easily hurt, also because of a REAL medical condition. You, more than most people should understand both situations, and I hope you do now, and if you are honest with this Mom, I bet she will too. If you need to make this choice for your daughter, then make it, make it LOUD and make it CLEAR. The autistic child will not hear it any other way, and who knows, it may be one of the motivators she needs to help her work harder to change her behavior, autistic children have to work very, very, hard in therapy to learn what comes naturally to your daughter, and then they need reasons to practice them in the real world. Don't beat this kid up with every time she did something right to say that she does not have a problem, who in the world would do any work at all on a problem if everyone treated them that way? Would you? If you weighed 300 pounds and lost 5, would you keep working at it if you were told by your doctor, so, you still weigh 295...
All the hush, hush, subturfuge junk you went through in your post about it being Mom's fault, and how expensive the gift was is just junk. These are two completely seperate issues. You have a hard choice, and so does your daughter, and any parent with a child like mine will understand, if you you are talking to them instead of us. If they don't, you would not like them even if thier kid was totally normal.
M.