Daughter helping special needs boy backfiring?

I'm a mom of 4 kids. My daughter, who is 10, and in 5th grade, is the oldest. She is an exceptionally kind girl, sweet, generous, all around lovely (not just a mom brag---that is truly her nature!). There is a boy in her class, let's call him E, who is special needs. I am not sure exactly what is wrong, but he struggles socially, has outbursts in class, and struggles to make friends. E also has a classroom aide, in addition to being pulled out for some subjects.My daughter, being kind naturally, would tell me that she would talk to him in class and sometimes play with him at recess, "because the other kids don't want to play with him". DD has told me that he is often loud, impulsive, and socially awkward, and sometimes she even doesn't want to play with him because he's hard to get along with. She understands that he has special needs, and that it's important to be nice to him. I always told her that I am proud of her for being nice to him and trying to include him, but she is more than welcome to play with her other friends too, friends who make her very happy.Now, my issue is this, and forgive me if this comes out terribly. My DD came home from a field trip today, very, very, very upset. She was excited for their trip to the zoo this morning, so I asked her what was wrong. She told me that everyone in class, a few days ago, got to pick their groups (within reason) and up until today, she thought she was being in a group with 4 of her friends from her class. Instead, the teacher pulls her aside this morning, and asks her to be her "special helper" and to be in a group with E, two other special needs kids, and their aide, for the duration of the trip. DD was shocked, because she wanted to be with her friends, and E especially stresses her out, despite her knowing that he has special needs. DD asked why she was put in a group with those kids, and the teacher told my daughter, "Oh, you are so good with E and *other kids* and so good at being nice to others when other kids aren't!" DD, not wanting to cause a problem, went on the trip in that group, and had a miserable time. E and others were apparently overstimulated easily didn't want to go in most of the exhibits, and DD had a terrible time.I am proud of DD for being nice to this boy, but she should NOT be forced or expected to help this boy out all the time, especially with the teacher unexpectedly putting her in an awkward position. I also found out that the teacher has moved DD next to him for the entire marking period, and despite her telling her teacher that he distracts her and annoys her, teacher keeps saying "Oh, be nice, he has special needs!" DD's teacher also put him at DD and friends' lunch table, where he also is disruptive and makes it hard for others to socialize.DD told me, "Mama, I want to be nice to this boy. I know he thinks and acts and learns differently because he is special needs, but he drives me crazy!" DD also told me that she was afraid to tell me up until now, thinking that I'd accuse her of being mean or not nice to him. I get where she is coming from, too. It's one thing to be nice to someone and try and take them under your wing, but it's hard when someone isn't socially apt---nor should it be my daughter's responsibility to be his guide/wingwoman.I'm going to try and meet with DD's teacher next week. I know the year is ending, but I want to nip this in the bud before the 5th grade festivities begin---picnic, 5th grade dance, their class parties, etc. Do any of you have any ways I can address this to her without coming off like a jackass, plain and simple? Are my feelings valid? I feel awful, but it's important to teach your kids to be kind, but to not sacrifice your own happiness, for someone else. via /r/Parenting http://bit.ly/2WI6tFq