A father grieving over the killing of his son resorted to harassing and stalking his mistress when she ended their affair, a court heard.

Paul Crittenden bombarded the woman with phone calls and texts and left stickers with the picture of his tragic son Tom, who died, aged 21, from a single stab wound in September 2011.

The 52-year-old businessman was said to have “shelved his grief” following the death of his “gentle giant” son.

Maidstone Crown Court heard Crittenden became overbearing and suffocating towards his lover when the relationship was no longer intimate.

He also threatened to reveal intimate photos he had taken of her. He told her he would leave “Tom stickers” on her house and car.

Prosecutor Bridget Todd said Crittenden and the married mother had been having an affair for more than 10 years.

He was said to have thought of his wife as a sister and his mistress as more like a wife. But the relationship with the victim began to deteriorate three years ago.

“Over a number of years his conduct became excessive and she described him as being possessive,” said Miss Todd.

“He stated on one occasion when she tried to end their relationship that he would never leave her alone and she would never be free of him.”

Crittenden, of North Lockside Road, Chatham, admitted stalking, causing serious alarm and distress, between January 1 and March 16 last year.

He appeared before Judge Jeremy Carey, who jailed his son’s killer, Caleb White, for 14 years in May 2012.

Crittenden, formerly of Marion Crescent, Maidstone, was sentenced to 10 months suspended for two years after the judge said there was powerful mitigation and an unusual background to the offence.

He wept as Judge Carey said he should thank the victim for her compassion, his wife who was standing by him and his loyal brother Keith who wrote to the court.

He will have to complete 150 hours unpaid work and pay £475 costs. An indefinite restraining order was made banning contact with the woman.

Passing sentence, Judge Carey said: “The background to this case is a most unusual one. No parent should ever lose a child in the way that you did.

“That should be no excuse for this offending but there are sufficient reasons for the court to take an unusual course in a serious case.”

The judge said Crittenden’s behaviour was “appalling and persistent”.

“That should be no excuse for this offending but there are sufficient reasons for the court to take an unusual course in a serious case" - Judge Carey

He added: “You sought to control and, on occasion, frighten the life out of her. You threatened her, confronted her, pursued her, grabbed her physically and in every possible and unpleasant way made your overbearing presence known to her.

“It is to her enormous credit that she has not only survived that appalling experience but has also not been vindictive against you.”

White, of Cornwall Close, Shepway, was cleared of murder but convicted of manslaughter.

He was said to have been wound up with jealousy and anger when he stabbed 6ft 3in tall Tom in Maidstone.