Larry King Files for Divorce from Wife Shawn After 22-Year Marriage

5:40 PM PT -- A source who spoke with Shawn this afternoon says she was blindsided by the divorce ... she found out by getting a call from TMZ. As for Larry's allegations, the source says the last time Larry was in the hospital, doctors said he might only have 3 days to live. The source says their estate planning lawyer had told them they needed to update their docs -- something they had mutually agreed to do -- and that's what Shawn presented to Larry recently when he was ill. She strongly denies doing anything that would compromise the inheritance of their 2 sons. We're told Shawn is "devastated" ... the news comes 2 weeks before their 22nd wedding anniversary.

2:25 PM PT -- Larry's divorce docs, obtained by TMZ, list the date of separation as June 6, 2019. That's interesting because we got video of Shawn, the very next day, at LAX. She talked about Larry's recovery from the heart attack, and didn't let on at all about any trouble in paradise.

1:51 PM PT -- Sources connected to the couple tell TMZ ... they have been having marital trouble for several years now. Larry has accused Shawn of infidelity. We're told that has created tension for a while now, but the breaking point was when Larry was in the hospital a couple months ago.

Sources say Shawn presented him with legal documents that would have given her certain rights to their property that would adversely affect the couple's 2 sons. We're told they felt she was trying to screw them out of their inheritance.

We're told the boys went to Larry and told him they were outraged by their mother's conduct -- presenting the documents -- and pled with him to get out of the marriage. We're told he followed their advice.