Kate Quigley's gonna be okay after overdosing in L.A. with friends ... an incident that left 2 of her fellow comedians and another woman dead.
The model/comedian revealed she's on the mend, saying ... "I'm still healing physically & mentally. But reading all the positive messages from u guys is makin me cry tnight."
She added she's grateful for all the support and love, and it's helping her recover in the hospital ... slowly but surely.
We broke the story ... Quigley was at a get-together last weekend in the Venice neighborhood where 3 people -- comedian Fuquan Johnson, comedian Rico Angeli and Natalie Williamson -- all died of suspected accidental fentanyl ODs.