My Husband May have Cheated on me UPDATES

So I am currently 22 weeks pregnant with me and my husband's first child. About a year ago me and my husband went on a break. He started fooling around with another women. After we decided to work things out he cut ties with her. Well about 3 months he ended up going to celebrate a friends birthday. I didn't feel like going. He messaged me an hour later telling me she was there. He asked if I wanted him to come back, but I told him I trusted him. He didn't come back that night. I was so worried. His friends went searching for him and found him crashed half naked in his car. They told me he was acting weird that night, but his friend is a recovering alcoholic so there was no liquor at the party. He has no memory of that night. Well about a week ago she contacted him saying she was pregnant with his baby. I cried and wanted to know if it's true. He told me he doesn't want to believe it, but he has no memory of the night. He said he didn't have alcohol. Just the coke(soda) that had there. She's been threatening me, telling me she's pregnant and we better cough up the money or she will beat my ass. Telling my husband she will have him thrown in jail if he doesn't pay child support for neglect. I'm so broken. I keep begging for the truth but he says he can't remember. He has spent the last few days trying to remember what happened and he's getting frustrated with himself. I want to believe he didn't cheat, but I don't understand how he would be acting weird if there was no liquor. I'm pregnant and can't handle the stress. She now has her family sending me and my husband death threats. I'm scared for our baby and our marriage!

I think some may have gotten confused. My husband calls almost all pop coke. Not the drug. The drink.

UPDATE: So I talked to his friends more and they swore to be there was no alcohol there. They did tell me they saw her lead him outside. They said they didn't want to get involved. Like how can you say you are his friends, see he's acting strange and let him go off with her without even checking out the situation. I've talked to him and asked does he think he may have been drugged or assaulted. He told me he really doesn't want to think about that being a possibility. His mom went through that, so I can kinda understand why he may not want to think about it, but we need to figure this out. Ive blocked her but I'm tempted to ask her what Happended. I'm so confused.

UPDATE#2: So I decided to unblock and call her. I know it was stupid, but I needed answers. She started calling me a bitch and a hoe and we were just yelling at each other. She told me she's taking us to court for child support. Well I asked her if the sex between her and my husband was consensual and this women said to me " I'm not saying anything that you will try to use against me when we go to court". Like she didn't admit or deny it. If it was consensual why would we use that against her? Wouldn't someone in that situation say yes it was? I've tried to talk to my husband about what she said and he said he doesn't want to talk about anything involving rape. He said it's pointless because even if he was raped there's no point of trying to fight for it and send her to jail. He said we will most likely lose so it's pointless. All he's planning on doing is trying to remember what happened. Also his so called friends (I'm still pissed at them) said they don't even know who invited her. This situation is stressing me.

UPDATE#3: So his mom came over. She was the only one who I could think could help us. My husband doesn't want to go to court if sexual assault happened because he watched his mom fight a case for two years just for him to get 6 months. He got emotional when she got here and we were all crying. She told him to stop trying to remember what happened until he gets to a therapist. We are filing a restraining order against her. We've talked and if the baby is his.... He wants to fight for full custody. I feel my husband was taken advantage of and that's not the babies fault. I'm hurting over this possibility of having to raise a baby by another women, but my brother was adopted. So I feel for the child. We are trying to take this one step at a time.