Kim Richards Arrest: What Drove Her to Drink?

It has scarcely been one full day since Kim Richards got arrested at the Beverly Hills Hotel for some unruly, belligerent behavior, but fans of the reality star are already searching for answers.

Wasn't she squarely on the wagon?

Didn't Kim insist every time we went to watch The Real Housewives of Beverly Hills online that she's sober?

So what caused her to get so wasted that she allegedly locked herself in a bathroom and then supposedly kicked a police officer upon being taken into custody?!?

Insiders close to the reality star tell TMZ that Richards has been struggling to cope with a few pretty awful things going on in her life these days.

To wit...

Her ex-husband Monty still lives with her… and is dying of cancer.
Her son Chad was released from UCLA Medical Center mere hours before the incident.
Kim is not receiving any child support and is suffering through some financial difficulties.
Kim is trying to plan her daughter Brooke's wedding.

But the straw that truly broke this famous camel's sober back?

On Wednesday night, Kim and Brooke watched part three of The Real Housewives of Beverly Hills reunion special. Seeing what Lisa Vanderpump and Lisa Rinnna said about her was positively crushing, this source says.

Kim thinks Vanderpump has been trying to drive a wedge between her and her sister for months.

TMZ reports Richards left Brooke's home and ended up alone at the Polo Lounge. She found some friends there - and the rest is unfortunate history.

After drinking far too much, Kim was booked for public drunkenness, resisting arrest, trespass and battery on a cop.