You state you haven’t been together long (seven months is not long) but are talking marriage, kids for the future. I personally feel that you are two kids who are not at any stage in life to be having such serious conversations and this entire thread is an example of it. You both like the IDEA of something but aren’t emotionally mature to understand what is involved in making it successful (on both sides). As others have pointed out, there is a distinct lack of trust (on your part) and disrespect (on his part). You wouldn’t enter a business arrangement on those terms so why throw your heart into something that could potentially hurt you down the line?
Not every person one becomes involved with needs to be a potential life mate. Some people are meant to enter (and exit) your life for but a moment. Learn a lesson from this. Learn about who YOU are; not what he’s capable, or incapable, of