Hollywood actor Jim Carrey introduced his Irish ex-girlfriend Cathriona White to "cocaine, prostitutes, mental abuse and disease."
The claim was made in a computer tablet note allegedly written by the Tipperary-born make-up artist two years before she took her own life.
The allegations were found on an iPad. It is not known if they were even seen by Mr Carrey.
Cathriona's alleged note was discovered by lawyers representing Ms White's estranged husband Mark Burton and her biological mother, Bridget Sweetman, with whom she had a troubled relationship.
The pair are claiming a wrongful death lawsuit against the Hollywood actor.
Cathriona White took her own life on September 28, 2015, not long after her 30th birthday.
Last Friday it emerged for the first time from his lawyers that Jim Carrey had paid Cathriona White an undisclosed sum of money to settle her claim that he had infected her with Herpes.
Regardless of that payment, Mr Carrey has denied infecting her with Herpes Simplex, claiming she had the STD prior to their relationship.
Mr Carrey's legal team claims the current attempt by her biological mother and her ex-husband to get more money from him amounts to extortion.
He is counter-suing Ms Sweetman and Mr Burton.
Mr Carrey and his legal team have dismissed their claim he was the cause of her death.
Mr Carrey's team says she took her own life because she felt guilty about extorting money from him two years earlier.
They also claim she was upset about a message from her mother sent two weeks before she died.
Carrey said it was a "mistake", in 2013, to settle the claims by Cathriona White and her former lawyer, Filippo Marchino, and vowed: "I will not give in a second time."
White's alleged 2013 iPad note describes their troubled relationship:
"You did good things for me, but being with you broke me down as a person, Jim.
"I was promise[d] Jekyll and instead I got Hyde," she allegedly wrote. Because I love you I would have stuck out Hyde all year and done everything he wanted to be with Jekyll.
"But you threw me away when you absorbed anything worthwhile that was left of me," the note states.
The note also addresses the issue of her contracting an STD.
"You have not thought about the stigma I have to live with for the rest of my life, you have not apologised or once asked is there something you can do to make it better, or even felt bad for it.
"Or even asked me how I'm feeling about it.
"Instead you did a whole lot of screaming and turned it round on me.
"Have you even once sat down and really thought how this affects me?
"I still love you and I believed that you sent that text because you cared about me.
"I was going to tell my lawyer that I didn't want to go any further with it, when I realised you changed lawyers and you were advised to text me.
"It wasn't coming from you at all.
"You probably hate me and are saying whatever is necessary.
"The decent thing to do: what is that? I think keeping quiet and private about it when I want to scream from the rooftops is a decent thing to do. You know what I want, and it's nothing to do with money.
"I didn't get a lawyer so I can take your money and I'm probably going to get in trouble for texting you.
"I'm sure you will use it against me, but I wanted to say this.
"You gave me hsv and hpv [Herpes Simplex]. I want you to apologise for it because you care enough to.
"I want you to understand that however little a thing seems to you, it ruins a girl's life.
"I want you to take care when you are with other girls, and pay attention to your body: your actions effect people. I don't want to be disrespected like you have been doing.
"Before you, I might not have had very much, but I had respect,
"I was a happy person. I loved life, I was confident and I felt good in my skin and was proud of most decisions I made.
"I met you, you introduced me to cocaine, prostitutes, mental abuse and disease.
"You did good things for me, but being with you broke me down as a person Jim. I was promise[d] Jekyll and instead I got Hyde," the note says.
Mr Carrey insists her STD accusations were false and that she was trying to get back at him for breaking up with her in 2013.
In Jim Carrey's counter lawsuit, revealed on Friday, his lawyers described a "cottage industry" based on extorting money from celebrities.
"Fighting the accusations is painful, time consuming, and extremely expensive-irrespective of the outcome of the claims," he said.
Mr Carrey described White as a "beautiful but immature and emotionally damaged woman" at the start of their relationship.
His lawyers allege that before her death, she threatened to go to the press with her claim he had given her Herpes unless he gave her "millions of dollars".
He settled her claim, paying her an undisclosed amount to stop her making the issue public, but insists strongly it was not him who give her the disease.
In 2015, two years after he paid the money, the couple got back together - despite their earlier legal battle.
Carrey's counter lawsuit claims he thought they would be together permanently after their reconciliation and that her suicide cut that short.
"On the verge of a lasting relationship and love affair came the unthinkable loss that was Cat's suicide," legal documents say.