11:23 AM PT -- Perry Farrell is issuing a public apology to Dave Navarro and his other Jane's Addiction bandmates after starting a fight onstage ... subsequently ending their reunion tour.

Perry tells TMZ ... "This weekend has been incredibly difficult and after having the time and space to reflect, it is only right that I apologize to my bandmates, especially Dave Navarro, fans, family, and friends for my actions during Friday’s show. Unfortunately, my breaking point resulted in inexcusable behavior, and I take full accountability for how I chose to handle the situation."

A source close to Perry tells TMZ ... the singer is "heartbroken" by his behavior, realizing he waited "too long to prioritize his well-being." We're told he was struggling with exhaustion and it took a toll on his physical and mental health.

The source says Perry had good intentions trying to power through ... but now feels like he let his fans and family down.

The Jane's Addiction reunion tour has been scrapped after Dave Navarro and Perry Farrell duked it out onstage in Boston over the weekend.

The band -- hitting the road for the first time in 14 years -- made a brief statement on social media Monday, where they confirmed they made the "difficult decision to take some time away as a group."

However, Dave made his own, blunter statement on behalf of himself and 2 other members of Jane's Addiction, Stephen Perkins and Eric Avery ... laying the blame at Perry's feet.

In a post shared on his Instagram feed, Navarro called out Perry's "continuing pattern of behavior" and "mental health difficulties" ... claiming these issues forced the band to discontinue the U.S. Tour.

He continued ... "Our concern for his personal health and safety as well as our own has left us no alternative. We hope that he will find the help he needs."

The Jane's Addiction concert in Boston ended abruptly Friday, when Perry appeared to throw a punch at Dave mid-show, shocking fans and his fellow bandmates.

The singer was restrained by members of the crew, and bassist Eric ... and was eventually pulled away from Dave.

Dave, Eric and Stephen expressed their regret they're not able to continue the highly anticipated tour ... but noted they could "see no solution that would either ensure a safe environment on stage or reliably allow [them] to deliver a great performance on a nightly basis."

Perry's wife Etty Lau Farrell hinted at the animosity between the band members Saturday, when she defended the singer, saying he was suffering from "tinnitus and a sore throat" the day of the show.

As Etty Lau put it ... Perry was frustrated with the volume onstage and reached a breaking point when the band started playing their song "Ocean" before he was ready.

Etty Lau applauded Eric for intervening ... but shared her husband "cried and cried" after the incident.

A tense situation for everyone involved that put a Stop! to the tour.