Gay rights campaigner Peter Tatchell has accused the British press of being “sensationalist” in its treatment of Tory Environment spokesman Gregory Barker’s marriage break up after reports that he had a gay affair.

Newspapers have been full of accusations over the last week that the Bexhill MP’s marriage to Celeste broke down because he had an affair with a man, a claim which he denies.

However the press has continued to pursue Mr Barker, speaking to his mother-in-law, neighbours, and friends of the alleged boyfriend who has now been named as antiques dealer William Banks-Blaney.

Celeste’s mother in law Georgina Harrison, told the Daily Mirror: “Of course it was a shock. It’s sad, but these days it’s not really unusual any more.

“It’s modern life isn’t it? Men seem to think they can get away with it now. Celeste found out in the summer so it’s still, you know, it’s hard.”

Mr Barker, a close ally of Conservative leader David Cameron, has since confirmed that he has separated from Celeste but says the rest is a private matter, a statement backed by his party.

Mr Tatchell said the politician didn’t deserve to be treated this way, “Some of the media coverage smacks of sensationalism and even a bit of a witch hunt.

“Mr Barker hasn’t done anything that justifies this intense press coverage.”

After the news broke, a source told the Daily Mail: “The affair has been going on a long time but Celeste has only just recently found out about it.

“She is absolutely devastated. It came completely out of the blue. Nobody had any idea that Greg was gay. She has dedicated herself entirely to supporting his career for years.”

The Daily Mirror, one of the first to break the news, claims that the affair has been going on for two years, Andrew Lamberty, named as a friend of the alleged couple, said: “I have known about this for quite a long time. Will and Gregory were expecting it would come out and were preparing for the worst.

“At the end of the day, you can’t find someone guilty of falling in love.”

The publication has now been blacklisted by the Conservative Party.

Many of the reports also concentrate on his relatively poor voting record, he opposed a gay adoption bill in 2002, and has previously backed keeping Section 28 before it was repealed.

But since then he has voted for civil partnerships, Mr Tatchell told PinkNews.co.uk there is no public interest in chasing the politician, “Since Mr Barker has not committed a criminal offence and no longer appears to be behaving hypocritically, I see no public interest justification for intruding into his private life and grilling of his friends and family.

“It is true that in the past he had voted against gay equality but recently seems to have had a change of heart and voted to support civil partnerships.

“If someone stops being homophobic I think wee need to show a degree of generosity and forgiveness.”

Mr Barker, who has three children with Celeste, has refused to speak to the national press, but told local paper the Bexhill Observer: “Sadly it is a matter of record that we had an amicable separation in July this year.

“Both of us abhor the tabloid intrusion into our private life.

“We are both very grateful for the local messages of support that we have received.

“I want to assure everybody that I will do my best to ensure it is business as usual in the coming weeks in my constituency.”