
Perkins, who is now in a relationship with fellow TV presenter Anna Richardson, says that she was unsure of her sexuality as a teenager, and throughout her university years had a long-term relationship with Rob, who she met while they both starred in a production of Bizet's Carmen in school.
The six-year relationship ended after Rob admitted he was gay and had cheated on Perkins with other men, leading to them both deciding to take an HIV test while on holiday in Florida.
Perkins eventually came out to her parents as a lesbian later in her twenties, but says she "truly loved" Rob at the time.
"I really loved him, absolutely," the 45-year-old writes.
"We shepherded each other through that odd stage of life where you move from your mid-teens to your early twenties. He’s such a good, kind man.
"To be a gay woman doesn’t necessarily mean you couldn’t have truly loved a man or truly enjoyed sleeping with men. Sometimes I think people are so absolutist and I wanted to pay proper respect to that relationship."
Of her relationship with Richardson - who herself was married to a man for 18 years before meeting Perkins - she says: "Anna’s just so much fun, and [when we met] I was in such a big [emotional] trough."
She continues: "If you look at my CV, you can’t imagine that person who is permanently gurning over a lemon drizzle could ever feel moments of despair and sadness like everybody else but I really was in a hole and I think she’s just so good at allowing me to have fun which I am extremely grateful for on a daily basis."
Perkins recently revealed that she has been living with a brain tumour for eight years, and in another recently-published extract from her memoirs she recounted the shocking homophobia exhibited by her doctor while she was receiving her diagnosis.
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