Irish lothario Colin Farrell has found himself at the centre of a heartbreaking love story.

An ex-boyfriend of the actor's current flame Muireann McDonnell killed himself two months after she began dating the actor, according to a report in The Sun.

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Muireann McDonnell and Colin Farrell in Italy

McDonnell, 21, met Farrell, 30, at a Dublin bar during the Christmas period after she and Knight had split.

A friend of Knight's told the paper: "They must have hit it off immediately. They began to go out. John was devastated."

Another source said: "He struggled to cope with her seeing somebody else. The fact it was Colin Farrell must have made matters worse. As time passed things got worse for John."

McDonnell was said to be devastated when she heard the news her former boyfriend had been found dead in his home.

She appears to be seeking comfort in Farrell: the pair were seen on holiday in Positano, Italy last week.

Friends don't harbour animosity towards the new couple, telling the paper: "Nobody in either family is assigning blame and there is no bad feeling towards either Muireann or Colin. John Marc's death is a terrible tragedy and it is a huge loss to all of us."