Why not hit it & quit it? But sounds like your looking for a relationship. Although, if she brings her kids around & tries to go out and put you in a situation where your out, and wants you to play the daddy role, I give you full on credit.
How you gonna be out there looking like a happy family & the kids aren't yours? Okay, granted some do that & it's cool. To each their own, but of she's forcing it on you cut her loose.
If not, play the part & hit that shit all you can.