Annalise Mishler says her ordeal with Chad's one of the most difficult things she's ever been through ... but it's being made way worse because he simply refuses to take responsibility for his behavior over the past 2 weeks.

Now, Mishler claims Johnson's out to ruin her life by posting false allegations to make himself look and feel better and make her look worse ... but she says it's very clear he's lying.

If you're unfamiliar, let's backtrack -- Chad was arrested for domestic violence and robbery last week after he allegedly got physical with Annalise. He addressed the situation the following day, admitting to getting angry and punching a hole in the wall -- which was seen on video -- but denying he'd put hands on her while also apologizing.

However, he followed that up days later with a concerning social media post depicting what looked like a makeshift hanging contraption, with the caption, "it'll be okay." The post sparked suicide fears and a welfare check ... and he was taken to a hospital for further evaluation less than 24 hours later after more troubling posts.

One of them included unfounded claims directed at Annalise, which ended with him writing, "All you had to do was hug me. You destroyed my life and it didn't even workout for you."

Johnson also made a YouTube video listing all the ways Mishler wronged him, essentially blaming her for his issues. She posted a response calling his vid "the most bizarre smear campaign attempt i've ever seen" and textbook manipulation.