A woman accused of stabbing another diner at a Ruth’s Chris Steak House in Manhattan made bail — but she’s still “not feeling good” because she believes she was only defending herself, her father said Thursday.

Joan Thompson, 41, was let go after posting $40,000 bail with help from friends and coworkers at Costco on Sunday, according to her father and public records.

Thompson was released two days after she allegedly stabbed a 24-year-old man in the back during an argument in the West 51^st Street steakhouse, leaving him with a pierced lung.

“She’s not feeling good,” dad Carlos Stapleton, 84, told The Post in a phone interview. “Anybody wouldn’t. When you’re the victim, how you going to feel good about something like that?”

Thompson is “real upset, but she’s OK otherwise,” he said. Thompson’s two teenage sons are also “upset” over the entire thing, Stapleton said.

Stapleton had previously told The Post his daughter was defending herself after the man attacked her and a cousin who she was dining with. The bail was unfair, he added.

“She’s never been in no trouble. That was very unnecessary,” Stapleton said.

An argument broke out in the steak house between a large group and staff, when one rowdy customer turned his attention on Thompson. The man was ready to hit Thompson when she stabbed him in the back with a steak knife, her father previously claimed.

The stabbing was caught on cellphone video, which was described by prosecutors in court on Saturday. The video allegedly showed Thompson standing on a chair shouting and making a stabbing motion toward the victim, prosecutors said.

After the attack, Thompson and her dinner companion fled the restaurant and ditched their bill. Thompson was tracked down through the name on her reservation and arrested after 2 a.m. on Saturday, according to prosecutors.

No one answered the door at Thompson’s apartment on Thursday. Stapleton couldn’t say why his daughter ran from the scene.

“Why that was done, I don’t know,” he said. “I don’t know what took place for her to leave.”

Thompson was charged with assault and menacing, but prosecutors said they might upgrade the charges after reviewing the victim’s medical records. In brief remarks over the phone on Saturday, the victim said he was “feeling great” after the incident.