A pregnant Cassie Ventura endured an excruciating grilling in Manhattan court Thursday — as Sean “Diddy” Combs’ lawyers dredged up scores of X-rated messages in a bid to blame her for his alleged abuse.

Ventura, 38, a mom of two who’s eight months pregnant, largely maintained a composed air as she was prodded about her sex life, drug use and other sordid details from her tumultuous decade-long relationship with the Bad Boy Records mogul.

Defense attorney Anne Estevao tried to cast Ventura as a willing participant in Combs’ depraved “freak-off” sex romps by having the R&B singer read scores of sexually explicit texts the couple shared.

“I’m always ready to ‘freak-off’ lol lol,” Ventura wrote in a Blackberry message to Combs on Aug. 5, 2009 — roughly two years into their relationship, when she was in her early 20s and he was in his late 30s.

The raunchy texts formed the backbone Estevao’s cross-examination of Ventura, who spent the two previous past days recounting in harrowing detail the abuse she allegedly suffered during her relationship with Combs, 55.

The defense at Combs’ federal sex-trafficking trial appeared to zero in on the intimate texts in a bid to undercut Ventura’s assertion that the mogul coerced her into the degrading “freak-offs.”

Jurors were shown one 2017 message where Ventura told Combs “I’m too excited” about one of their upcoming “freak-offs.” She also messaged Combs that she forgot an iPad — which she testified they used to record the sex marathons.

Combs once texted Ventura to “have fun, impress me” when she was on her way to a sex shop to get supplies for a “freak-off,” jurors learned.

The court also saw messages between the couple sent on May 26, 2017 — near the end of their relationship — about her run to a sex shop called the Pleasure Chest. Ventura testified that when she went to the X-rated store, she “would get different sexual supplies. Lubricants, outfits.”

Another message showed the pair appearing to try to avoid getting pregnant after Combs suggested having “one of our nights.”

After one message was read out, Ventura asked for a break and grabbed her pregnant belly with both hands.

At one point, she smiled when Estevao brought up a loving email she wrote to Combs just a few weeks after her 21st birthday party.

“It’s making me giggle because it’s from 2007,” Ventura said.

The email expressed how “grateful” Ventura was to be in Combs’ life, but also how she felt he was “constantly weary (sic)” of her.

Ventura’s husband and the father of her children, personal trainer Alex Fine, sat stoically in the courtroom gallery looking as she described when she fell in love with Combs.

Ventura kept things cordial with Estevao – even sharing laughs with the lawyer – early in the day, but her answers grew shorter and shorter as the hours dragged on.

“Do you have any questions for me?” Ventura asked at one point as Estevao read from another years-old text exchange.

Ventura previously testified that she participated in the “freak-offs” to please Combs — and because she wanted to avoid his anger which often resulted in him beating her.

But Estevao – beyond attempting to paint Ventura as game for the baby-oil-filled and humiliating “freak-offs” coordinated by Combs – also tried to cast her as toxically jealous of Diddy’s harem of women and stuck in a cycle of dangerous heavy drug use with him.

The testimony grew more tense when Estevao implied the 4-star Golden Door resort in San Marcos that Ventura considered going to during 2017 was a drug treatment facility.

“It’s not a rehab facility, but yeah. It’s like a spa,” Ventura said back. “Yeah, I come to find out, yeah.”

Ventura testified that Combs and her called each other “get high partners.”

She admitted that she once went to a rehab in Sedona, Arizona in 2017, but it didn’t stick.

After she left the rehab, she took part in another “freak-off” with Combs, she said.

“Part of the reason you wanted to participate in the ‘freak-offs’ was to have your time with him? It was a special time with him you cherished?” Estevao asked.

“Yes,” Ventura replied, repeating the one-word answer when Estevao then asked, “It was a time to connect with him?”

Ventura previously said she developed an “on-again off-again” opioid addiction, relying on the pills to help her feel “numb” after taking part in the “freak-offs.”

One text from 2009 appeared to show Ventura starting to push back against the sick sessions — and her fear that Combs was using her for sex.

“When we used to freak-off when we were so in love, there were no questions asked, it felt right, like it literally made sense for the next step in our sex life together. I get nervous that I’m just becoming the girlfriend that you get your fantasies off with and that’s it,” Ventura wrote.

The marathon grilling drew fire from federal Judge Arun Subramanian, who chided the defense for their slow pace – and then grew peeved when the lawyers tried to push for an extra day of questioning.

Subramanian didn’t budge, noting both sides agreed ahead of time that Ventura’s testimony would be completed by the end of the week.

He told the defense team they would need to finish up with her by Friday morning, but he said he might give them a little more time after lunch.

Combs lawyer Marc Agnifilo said he was surprised to hear there was a hard deadline: “This is a critical witness in a case that involves a life sentence.”

Follow The Post’s live updates from Sean ‘Diddy’ Combs’ sex trafficking trial in NYC

Combs has pleaded not guilty to one count of racketeering conspiracy, two counts of sex trafficking by force, fraud or coercion, and two counts of transportation to engage in prostitution.

He could face life in prison, if convicted.