Amy Winehouse leaving her London home to visit her husband Blake in prison. London, England - 27.03.08

The troubled singer arrived at London's Pentonville Prison on Thursday (27Mar08) wearing a large heart-shaped badge with her husband's name emblazoned across it.

But the Back To Black hitmaker was turned away at the gates of the facility because she had missed her appointment.

And British newspaper The Sun reports that the star's erratic timekeeping is putting a massive strain on her marriage.

A source tells the publication, "Blake is getting really wound up by Amy. Her visits are less and less frequent - and when she does visit, she is late.

"He has told Amy he wants a divorce. Part of that is about getting her to visit. But he's closer to going through with his threat."

Blake Fielder-Civil, has been held behind bars since November (07) on charges of assault and attempting to pervert the course of justice.

Source: WENN