Kaley Cuoco ''felt she had no choice'' but to split from Ryan Sweeting.

The 'Big Bang Theory' actress, who recently filed for divorce from the professional tennis player after 22 months of marriage, reportedly decided to end their relationship after he entered a Boston rehab facility last month in a last-ditch effort to get treatment for an alleged addiction to painkillers.

A source said: ''She didn't want to get divorced, but felt she had no choice. She couldn't fix him. He wasn't the man she thought he was.''

The blonde beauty is said to have known about Ryan's past issues with drugs when they got engaged.

The insider added: ''He was clean when she met him and honest about past troubles, but then he'd relapse. She got tired of the ups and downs.

''She supported him, but she said he couldn't make the commitment to get sober. He'd tell her he was working on it, and instead go and get wasted.''

Ryan allegedly got hooked on prescription drugs again earlier this year after sustaining another tennis related injury.

The source shared: ''Kaley told friends doctors prescribed something that he was taking too much of. That was when it went downhill. She decided to pull the plug.''

The actress is ''ready to move on'' and ''isn't wasting any time with ending the marriage,'' but has privately vowed ''she's never dating again.''

The friend told Us Weekly magazine: ''She is so down about any kind of future relationship. Kaley is devastated. She can't believe this is happening. She really did think it would be forever.''