So many points to consider in this thread.
I have a disability and chronic pain and understand how hard it can be without help. If that was your reason for wanting to stay with your parents then given that your OH is away so often I could understand it, however it seems your choice to live with your parents is unrelated to your disability.
You sound very afraid of change, afraid to live alone (most women do not feel unsafe home alone) and doubting your ability to make new friends. The army community is generally a very welcoming and supportive one, especially as everyone is in the same position as you. You'd probably make friends very quickly. Change is scary but branching out on your own and moving away from childhood friends and family is all part of growing up. Even if you didn't move, your friends may well do as they embark on their own careers and relationships so there's no garauntee they will always be around anyway.
You paint your OH as disinterested and non commital towards your child, yet you also say he is pushing for more commitment, marriage and living together. It's awful to say your DD doesn't like your OH. It's more likely that she just hasn't spent enough time to bond with him yet.
You are placing a lot of importance on your right to see your parents regularly and their right to see their grandchild regularly, but you don't seem to place the same importance on your DDs right to see her daddy regularly and his right to see her. It's great that your parents have a close relationship to your DD but that shouldn't trump the relationship she has with her dad.
At best it's naive to go into a relationship with someone in the army and yet not be willing to commit to an army life. A family life is especially important to someone in the army, it gives them a slice of stability and an anchor amongst all the upheaval and uncertainty. If you didn't want to live away from your family you could compromise by getting your own home near them, at least then you and your OH would have somewhere to call your own, and you could still visit your parents during the week. You don't seem willing to compromise though, you sound like you either want him to leave the army (which is unreasonable since you knew from the beginning that he wanted to be in the army) or carry on with things as they are even though you know he isn't happy and that his relationship with his DD is suffering because of it. I don't think he is BU at all by wanting more commitment. I think you really need to ask yourself whether you really want to be with him.