Historically its very common and its very likely you or the child will want to know about you or the child. Your gonna have responsibility for the child whether you like it or not. You can give input on abortion but its going to be the womens call. Even if aborted its going to be a possibility that will haunt you for the rest of your life. You don't need to marry to do any of that but you can get divorced if the marriage does not work out. That being said marriage is not an effortless thing, much less when adding in child rearing. Marriage can be nice and it can be awful and sometimes in the same day. Honestly its almost impossible for anyone outside of the relationship (friends with benefits is still a relationship) to say as we have no idea how you actually talked with her and what lead up to it. Obviously it sounds like a condom was not used so im not sure what you expected honestly. Maybe you were not as honest and forthright as you make it out to believe or maybe she was delusional or hoping for something that wasn't. Seriously though. condoms.