I can tell that you're a smart person and that you've really looked at this very realistically. Every question I had in my head was answered by your attention to detail, so this is the biggest factor in the whole situation: you're thinking it through and not in denial about the task at hand. Especially that you've factored in if something doesn't go right with the baby and there are extra expenses. Good call on that one.
Unfortunately, that doesn't mean your girlfriend has the same ability or is at the same place as you. I wouldn't assume that she won't come around to the practical plan that you've outlined, but I don't think she's there yet. Everyone operates on their own timeframe when it comes to adjustment. You've got the financial issues at hand and she has the new mom thing.
New moms are usually pretty fragile in the ego department, and want the privacy to make their own mistakes and figure things out without people who know more about parenting looking over their shoulder. Even if you want help and the family around...there is still this little thing inside where you're afraid you're going to do something really stupid, everyone but you will know it, and no one will tell you. This stuff is much bigger in your mind than reality, and it usually fades soon after birth. Being with your parents instead of her own might be touching upon this fear.
I think that your plan is good, but that she won't go along with it....this year. How about getting a lease on an apartment together and get everyone settled. Then next year maybe you can move in with your folks and get your feet on the ground. She'll have a much better understanding of the reality of life with a baby and the expense involved, and how nice it is to have help around. Your family will be established and you won't have so much to loose. She does have a point about having your own space to bond as a family together...that will be easier in your own place. You'll both have a better understanding of what your needs as a family are. Things will be tight, but maybe not as tight as possible....you've planned for the worst, but all the worst things won't line up and fall on you.
So, to sum up: I'd try to work on the apartment together for a year....talk that out and give it a chance. I think you'll both have a much greater appreciation for what your family will need in all areas.
My best to you.
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