Kaley Cuoco and Ryan Sweeting ''seemed miserable'' on their recent dates.

The 'Big Bang Theory' actress and her tennis player spouse confirmed on Friday (25.09.15) they have separated after 21 months of marriage, and insiders say they had tried to reignite the spark between them, but there was clear ''tension'' whenever they went out together.

A source told People magazine: ''The few times Kaley and Ryan were out together recently, the tension was noticeable. You could tell the honeymoon phase had ended.

''It seemed they were trying to work out their marriage by going on dates, but they both seemed miserable.''

Following news of the split, Kaley praised her ''incredible friends and family'' for their support.

Posting a picture collage on Instagram, she wrote: ''I have the greatest friends and family on this earth!''

While she did not reference Ryan, Kaley's message comes just days after her representative revealed the split, saying: ''Kaley Cuoco and Ryan Sweeting have mutually decided to end their marriage. They ask for privacy at this time. No further statement will be issued regarding this matter.''

The 29-year-old beauty also deleted all traces of her estranged husband on Instagram and unfollowed him across her various social media accounts.