Feeling like a failure and my princess isn't even here yet!!

So I need advice. Im sorry this post is so long but I really need advice as to what to do and how to handle my situation. I fee likenim damned if I do and damned if I don't... what would you do?
I hate to admit it but I am 26 and I am pregnant by a 19 year old... that's a whole other story I won't even get into. Well just leave it at bad decision making skills on my part... Any way... I have a high risk pregnancy and have had to see my regular OB every two weeks since I became pregnant as well as my high risk OB once a month. Now that I am 32 weeks the high risk Dr. Would like to see my regular OB once a week and still remain seeing him once a  month. I have insurance through my job that I pay for which is 100 dollars a month. My copay is 35 dollars everytime I see a Dr. I also have a $350 dollar universal labor and driver fee and on top of that I have prescription that cost me $30 dollars a month. It's an injection I have to be on the whole time I'm pregnant). I work 80 hours every two weeks and after taxes, health insuranc, dental, short term disability, life insurance, 401k, car insurance and a $100 garnishment I bring home on average 450 dollars every two weeks... I pay 300 a month for rent and about 100 for electricity my phone bill is 80 and it's a 40 a week to fill my tank up. That leaves me with $260. Now once I incorporate my deductibles and prescription I'm left with 55 dollars to live off of for the month. 
Her father works at a car detailing shop and brings home about 700 every two weeks. He does not have a car so he doesn't have to pay for car insurance or gas. He walks to work it's 5 minutes from where he stays... He opted out of any benefits from his job he said he don't need them. He stays with his brother and he pays him 50 a weeks so out of the 1400 he brings home a month his only responsibility is 200 in rent to his brother. His brother and sister in law get food stamps and they let him eat their food. 
He knows I'm struggling. I was selling my PS4 and instead of offering to help he offered to buy it from me... I feel like even though we are not together the expenses I am incurring for this pregnancy are both of our responsibility. He has repeatedly told me he will help but every pay day it's nothing but another excuse why he cant this week. Examples: it's his birthday, it's his mom as birthday, it's Christmas, it's New Years, he has to buy a tux for his brothers wedding.... Then when I get mad and tell him I don't have the option of just putting it off till next week he tells me it's not his responsibility or his problem and she ain't his responsibility until she gets here. Then says it's not his fault I work instead of collecting food stamps and getting Medicaid... The state won't approve me for either, they say I make too much money... 
I'm handling it and doing it and have been and will continue to because that's what grown ups and mothers donwe figure it out and make a way when there doesn't seem to be one. My problem singe wants to be a the baby shower and come to my appointments and ask for pictures of the ultrasounds and wants to be in the room when she's born. I fee like why should I let him enjoy any of that when he hasn't helped pay for any of those services. He wants to enjoy all the fun parts of being a dad but says she ain't his responsibility till she gets here...
Part of me says just pray about it, put it in Gods hands and let God do what needs to be done.. Dont keep him away let him come to the appointments let him enjoy the ultrasounds and be there when his baby is born not only for him but for her. Like just bite the bullet and be the doormat. My problem with that is I can handle him being inconsistent and breaking promises to me I don't want to allow him to be that way with my child and I feel like he will end up being a disappointment to her more times than not because he never does what he's says he's going to do.
The other part of me feels like I am not obligated to let him enjoy any of it. I want to tell him to get a court order for a DNA test and take me to court and fight me for his rights. Not to be  vindictive but because I feel like that is the only way he is going to grow up and take care of what he needs to. If he wants to seebherbthat bad and be a part of her life he will take that route and prove he deserves his rights or he won't and I'll know she obviously ain't worth it to him. My problem with that is when she gets older I will have to explain to her why he's not around if he doesn't do the right thing and I fear she will blame me. 
My dad is my best friend and my heart hurts so bad thinking about having to raise a little girl not knowing the love of a father. I have a great dad he sacrificed so much for his kids and that's all I want for her. He don't realize how messed up how priorities are and I really don't know what to do any more... I cry every time I think about it. I honestly feel like I have failed her before she's even been born. 
What would you do??