Ruth Carr attacked Alan Allan, 34, at about 09:00 on 25 January last year after an argument.
Carr, who was wearing only underwear at the time, had claimed Mr Allan had sexually assaulted her.
A jury at the High Court in Glasgow rejected her claims of self defence and convicted her of murder.
Neighbour Jill Strachan told the trial how she became aware of "a commotion".
The 39 year old said: "There was a lot of shouting...to-ing and fro-ing.
"Initially, it seemed to be all about money.
"When the accused saw that she had an audience, she said something else.
"I remember her shouting 'phone the police, he has raped me'.
"She was wearing pink pants and a black bra."
Ms Strachan said she did not believe Carr's claims of being sexually assaulted.
She said she thought Carr was then punching the man, who she had never seen before.
Miss Strachan added she did not at first see a weapon. However, after hearing the victim in apparent pain, she then saw a knife hit the ground.
Mr Allan died at the scene. He suffered four stab wounds - two of which were considered life threatening.
Judge Lady Stacey deferred sentencing for reports until 10 February in Edinburgh.
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