I went to Disneyland with friends (2 adults, a 3 year old, and their infant) and I did a lot of stuff solo anyway because some of the rides weren't under 3 friendly or they were busy taking the kids to the restroom/breastfeeding. It was okay, I got solo rider status on some and no one even worried that I was alone. That being said, I travel solo a lot and have found the joy in it. If you feel uncomfortable that people think you are alone, just say your group wasn't interested in that ride, or they are sick, or something like that. But really, most people are not judging you...its all in your head!