I'll admit, I found this movie very boring and was zoning out a bit by doing other things and half watching out of curiosity as to the ending.
I missed the part where her mother (Lilly Tomlin) says she didn't just get a random sperm donor on a NJ train.
I missed the rest of the scene, does her mother tell her who her father was? Was it the Russian guy? Or she really didn't know?
"Man without relatives is man without troubles." Charlie Chan
I don't think it was the Russian guy.
What I took from that scene was that Susannah was promiscuous and did in fact have sex with a random guy on the train and got pregnant, I think what she had lied about was that she had planned to get pregnant by some random guy she didn't know when in fact, getting pregnant with Portia was unplanned, she had just wanted sex and that's why she didn't get the guys name, she had believed at the time that it was just a quick hook-up and of course, after finding out she was pregnant, she regretted not getting his name.
She had always told Portia that she had only wanted to get pregnant and that's why she had unprotected sex with a stranger, she told her that she had wanted to be an empowered single mother, she lied. She literally told Portia that getting pregnant had been a mistake, albeit a happy one.
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Just because YOU don't like something doesn't mean it is empirically not good.-Tina Fey
Thank you for clearing that up, the mom was inventing a narrative that fit the way she wanted to be viewed. A very ironic lie, both to the world and to herself.
"Man without relatives is man without troubles." Charlie Chan