I'm 25 and mostly go with just my mum, but I've done a solo trip in the past.
Either way, I never have little kids with me.
And I absolutely adore meeting characters, that's pretty much the main reason I even go.
Characters respond so well. They've never treated me weirdly because I'm not a kid.
Yes, some parents give me weird looks "since Disney is for kids".
Obviously that statement isn't true, but there are always people who don't get the meaning behind Disney.
However characters never treat me weird for it. If anything they go a little extra during the meet.
But to give you a little tip:
Don't expect on planning to meet any character besides the ones mentioned on the programme.
Mad Hatted and Alice for example: yes they are quite common, but there are plenty of days that they won't come out. Please don't get yourself to excited, you might get disappointed.
Just plan on meeting the characters mentioned on the programme, then everyone else will be a bonus.