The `Price Tag` hitmaker is openly bisexual and says her family have always been accepting of her sexuality, even though she was regarded as "rebellious".
She said: "It is important for me to be open and honest about it. My mum and dad have known for years and were super cool, my sisters made jokes about it because they were married with kids and I was the rebellious one. I had a girlfriend and tattoos. I was like- hardcore.
"Because I haven`t tried to hide it, people have gone, `Oh she`s so cool about it, so we`re cool about it.`
"How old was I when I had my first girlfriend? Dunno. 17? It wasn`t a girlfriend, more my first girl experience."
Jessie - who refuses to say if she is in a relationship with anyone at present - admitted she finds it "sad" that people find it odd that she doesn`t drink alcohol or take drugs.
The 23-year-old star added to Britain`s Glamour magazine: "Drugs and alcohol are not the epitome of an amazing life, they`re actually glamorised way too much.
"People go to me, `Oh my God, you`re in the industry and you don`t take drugs?` It`s weird to me that it`s seen as un-normal. It`s quite sad."