The X Factor judge has booked a flight ticket to America and is said to be looking for an apartment in Miami, Florida.
A clip of Contostavlos performing a sex act on MC Ultra - real name Justin Edwards - leaked last month, prompting the singer to obtain a gagging order.
"The sex tape scandal has hit her hard. Behind closed doors she's been an absolute mess and she's found all the attention over it really tough to take," a source told the Daily Star Sunday.
"She's desperate to get out of Britain and away from it all. Everywhere she goes here people are whispering and making jokes about the tape, which really upsets her. Going to America means she'll be able to escape everything for a while.
"Tulisa has even considered moving to America full-time and quitting life over here. She is desperate for a fresh start and she thinks this could be the answer. She's already on the hunt for somewhere to live so no one would be surprised if she turned her back on Britain for good.
"She says she's never been happier than during the month she had in Miami. She was really relaxed, had fun with friends and made some great industry contacts. No one can blame her for wanting to go there for good, especially with all the sex tape scandal rumbling on in the UK."
The scandal is also said to have jeopardised her rumoured relationship with Skins actor Jack O'Connell.
"Jack has been a massive support but Tulisa is convinced he has judged her just like everyone else," the source added. "She wants to start a new life and thinks staying with Jack will mean she won't be able to move forward."
US rapper Terius Nash will reportedly help Contostavlos find a suitable home in Miami and has already recommended a long-term let in the Roney Palace Condo complex.
The former N-Dubz star apparently recently left a Drake afterparty early after feeling embarrassed about the sex tape.
Watch Tulisa Contostavlos discuss her sex tape below: