Conservative MP Dame Caroline Spelman says she intends to stand down at the next election after months of abuse and death threats over Brexit.
The 61-year-old MP for Meriden said the "intensity of abuse arising out of Brexit" had crystallised her decision.
She said the worst abuse had come since moving an amendment earlier this year to demonstrate there was no majority in Parliament for a no-deal Brexit.
"I have never experienced anything like the last few years," she said.
Ms Spelman, an MP for 22 years whose constituency sits in between Birmingham and Coventry, said: "Myself, my family and my staff have borne an enormous brunt of abuse and I think quite frankly we've had enough.
"The anonymity the internet affords allows people to say things which if they said it to your face or they wrote it down, would not be legal."
Ms Spelman said she also had to consider her front-line staff's welfare.
The former environment secretary also rejected being labelled a Conservative "rebel", saying the party's chief whip clarified to her she could vote with her conscience in the House of Commons on Wednesday, supporting a bill opposing a no-deal Brexit.
She also backed Prime Minister Boris Johnson to get a deal with Europe, but, she said, a general election was needed to "clear the air".
"The question is when, and I think Boris should have the chance and have the time to get a deal," she said.
Ms Spelman added: "My constituency voted Leave and I am respectful of that.
"But I believe it is very much in their interests that we leave with a deal in an orderly fashion."
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