Caroline Schwitzky of "90 Day Fiancé" is still trying to wrap her head around the acquittal of her ex, Cole Goldberg, who had been accused of trying to kill her ... and she feels betrayed by the system.

As you know ... Cole was acquitted of attempted murder last month. Schwitzky accused  Goldberg of attempted murder back in 2022 -- she claimed the two got into a heated argument at the Boca Bash that year after she dumped Goldberg, and accused him of holding her head underwater.

Caroline tells TMZ ... she was so floored Cole was acquitted ... she needed several weeks to gather herself to speak out -- and says she still can't process that he won't be held accountable.

Instead of taking his chances with a jury, Goldberg opted for a bench trial, in West Palm Beach, Florida -- and Judge John Parnofiello said in his determination there was too much inconsistency in witness testimony ... and enough reasonable doubt to acquit Goldberg.

Caroline -- who's since married and is the mother of five -- tells us she feels screwed by the system and has learned firsthand “it’s not what you say … it’s what you can prove.” She also noted her disgust for what she felt was Cole's public gloating in the wake of his acquittal.

Caroline has since dedicated herself to being a victim advocate -- and using her celebrity to help other women who are in abusive situations, through outreach.

After his acquittal, Cole's lawyers, Heidi Perlet and Marc Shiner, told TMZ ... "We are all relieved and grateful that this four-year ordeal is over. We had every confidence in Judge Parnofiello's ability to be fair to both sides of the aisle and to follow the law."