Hi M.. I deal w/ this a lot w/ my 3-year-old son. When we go to parks or play areas and he runs around w/ older kids and they shrug him off (and sometimes aggressively tell him to leave them alone), I worry that it'll hurt him. It doesn't hurt me as much as it seems to hurt you, but I completely understand your feelings. I just tell my son (even though he may not completely understand) things like this: "You know, it's okay to play alone sometimes. You can't be friends with everybody, but just be nice." I think you're right that it's a part of being a mom, and our kids will deal w/ all types of rejections for the rest of their lives--from love interests, schools, jobs, and things like that. So, it's just good that they get a little practice when they're young. I think the key is helping them to remain confident in themselves and not to get down and out about it to the point where they can no longer function happily.
One time, my son was aggressively rejected by a group of kids at the park and so his father and I encouraged him to keep playing on the play structure--w/ or w/o them--and eventually, they were chasing him around, wanting to play w/ him! We didn't tell him to return their rejection; although, that was very tempting. And in the end, they all played happily together. It won't always happen like that, but it made me smile to think that they hadn't crushed my little boy's heart and that he was able to forgive them and keep playing.
