How Do I Stop Oneitis for the Mother of My Child?

I'm not sure what details you guys need to know, so I'll give a quick overview:

I'm 19. She's 18.

She's due around August 1st.

I've got BPD and started meds back in March.

We're from Tennessee. Relatively stereotypical southern families involved. We're both from lower middle class families but I've been "adopted" by a couple of upper class families of friends and have lived with them since age 17.

She's got daddy issues, I've got issues with both parents.

We both were about as "high school love" as can be, totally obsessed, until she got pregnant. She got a bit distant and I went way too obsessive, BPD had been around a bit before but I could deal with it. It came in full swing to the point where I had to be hospitalized for three weeks for malnutrition, drug use, lack of sleep, etc.

I had no trouble partying and forgetting women before her. I met her last summer and have been captivated ever since. I don't know why. Other women have come and gone. She's pretty, but not exceptionally beautiful. She's smart, but not exceptionally genius. She's into the same kinks as me, but not all of them. She's often more trouble than she's worth but I've always been obsessed. Banging other chicks, hitting the gym, taking a weekend with the guys, none of it has lessened how I feel towards her.

We've discussed that I still have these feelings towards her and she has told me that they are 100% unrequited. She has said her emotions are all over the place because of being pregnant and she might fall back in love when she's back to normal.

I think this is just some kind of manipulation and am considering telling her that unless she wants to talk about our baby, she shouldn't contact me.

You guys normally have solid advice. I'll answer questions or whatever you guys need, please help me with this. I'm in over my head and could use some advice.