Her trial hasn't even started yet, but those who know her bast say Lori Loughlin has accepted that she'll soon be going to prison.

And that's not just defeatist pessimism on Aunt Becky's part.

Legal experts and insiders close to the situation say the actress will most likely be forced to do some time as a result of her role in the college admissions bribery scandal.

Loughlin refused a plea deal, which means she's unlikely to get off with a slap on the wrist like Felicity Huffman, who served a scant 12 days behind bars.

So with her fate more or less sealed, Loughlin has reportedly been dividing her time between two very different pursuits in recent weeks.

By day, Lori has been preparing for prison by taking martial arts classes and meeting with a consutlant who's done hard time.

By night, Loughlin has been indulging in every vice under the sun in order to distract herself from her future incarceration.

A source tells Radar Online “on a mission to self-sabotage ahead of her sentencing."

“She seems to have given up and just wants to go down with a huge bang at this point," the insider says.

The informant says Loughlin is particularly struggling with the fact that she may have put herself in this position by refusing to accept a plea deal -- a decision she apparently blames on her husband, fashion designer Mossimo Giannulli.

“Lori turned the corner and backed out of considering a guilty plea due to her husband’s insistence,” says the source.

“She had been talking to her lawyers about it, but her friends and family were encouraging her to pursue a plea deal. She’s only listening to Mossimo though.”

Seems like if she were to regret anything it should be committing the crime in the first place, but what do we know?

“There’s still a delusional side to Lori that’s keeping her fingers crossed for a miracle, but she’s scaled way back on legal meetings and preparing her defense ahead of the trial – and that’s a huge sign she’s accepted her and Mossimo’s fate behind bars," the source claims.

“Lori’s convinced she’s been totally scapegoated and is walking around in a furious fog, trying to make the best of things day-to-day," the insider adds.

"She almost doesn’t care what happens to her now, or so she says, so she’s doing what the hell she wants and saying a big ‘f--k you’ to her critics.”

Hmm ... seems like a bigger "eff you" would be holding it together and using her final days of freedom as an opportunity to things right with her daughters.

But again -- what do we know?