I thought it was odd that people seemed so angry and surprised, it's been pretty clear she fancies the Doctor for a while.
and she wanted to take the chance, cause there's a life waiting for her, and she can't live her life without first well, dealing with the Doctor, with the fantasy she's had her entire life. I think eleven and amy are still defining their relationship and just cause she's tried to jump his bones doesn't mean they have to go the unrequited love road now.