Stay or go? (Sorry it's long)

So, I'm supposed to be moving with my aunt here shortly from Colorado to Maryland..but this guy (who lives here in CO) I've been talking to is asking me to move in with him. We've known each other only for three months but he's a nice guy. Of course he has flaws and a past with 2 kids and an ex wife, no one is perfect. But the problem im having is being in his kids one lives one day and thinking that someday I may fall in love with them(I love children) and if anything were to happen im alone with no family, and would feel bad for one day just leaving them. On top of that every woman I know has told me to try not to make the same mistakes they made, which is moving in and starting a life so quickly with the wrong guy. On top of that, he's kind of acting like we're supposed to married and he's saying he's "falling for me". It's almost like pressure...but in a passive aggressive kind of way? I'm not sure what to do...