Hi Orchid,
It's my personal belief and i could be wrong but i think anyone who is saying things such as hinting at marriage so quickly into the actual relationship is probably someone who is fickle with their emotions. It difficult to gauge this
The only way you're going to have any answers to this question is by talking to her. You said yourself; you have found an "adult" - so why not have an adult conversation and talk to her about your expectations, hopes and dreams for the future - and