Dating El Chapo means always having to say you’re sorry.

Newly released text messages between Joaquin “El Chapo” Guzman and his mistress offer a look inside the drug lord’s twisted love life, showing he sent her love notes mixed with death threats — and that the two may share a secret love child.

“Look, the mafia kills people who don’t pay or people who snitch,” Guzman wrote in one 2012 message to Lucero Guadalupe Sanchez Lopez that was released in his Brooklyn federal court trial Thursday, “but not if you’re serious, love.”

The message was supposedly a warning to Sanchez — who worked in Guzman’s drug empire while having a years-long affair with him — to keep a low profile because people were talking about her.

“Lies are what cause problems. Don’t lie and people will always see the good, love. Always remember that. I’m telling you this because I love you,” he continued.

In response, Sanchez, 29, insisted she was “not doing anything bad” and gushed about how much she loved him — but while testifying, she said she was “feeling threatened” and was worried “he could actually hurt me.”

Sanchez told the court that whenever she went to see her married paramour, Guzman’s cronies would cover her eyes and take away her mobile phone.

She also recalled an occasion when Guzman’s secretary walked in as they were eating and told them an associate named Tio Virgo was dead — which she took to mean Guzman had ordered him killed.

“He turned around and looked at me in a slow demeanour and then he said something I did not like,” she told jurors.

“He said from that point on, whoever betrayed him, they would die. Whether they were family or women, they were going to die.”

Meanwhile, other texts shown to jurors appeared to confirm rumours that Guzman and Sanchez had a child together.

“This is your son,” she wrote in one 2012 message.

“Hello, my king. I congratulate you because you’re a real man,” Guzman replied.

In another message, he said he’s sending “kisses” to her and “Rubencito” — as the lovers also carried on a conversation about weed sales.

“A kiss for each,” he messaged her alongside two “wink” and “kiss” emojis. “For you and for Rubencito, two for you.”