As the devil’s advocate here: What if the woman were, in fact, very attracted to the man, even in love with him. She desired him sexually, but she would not act on that unless the possibility of a LTR were there, meaning he had to be jewish. Perhaps she believed, being told by him, he were jewish, when they first met.
If she hadn’t believed him to be jewish, she wouldn’t have spent any time with him, wouldn’t have fallen for him, wouldn’t have let herself become aroused and excited by him.
In every other way, he seems to be her dream-come-true. She decides to have sex…
She spent her time and emotional resources getting to know this person, based on his fraudulent representation. She lowered her religion-based defenses to him. He told the lie in order to get just this opportunity. He valued her company, and enjoyed it by lying to her. He knew she would be disappointed, even crushed. He chose to do that to her. He knew she wouldn’t spend time with him, much less have sex, if she knew he wasn’t jewish. He specifically maintained that lie in order to have her submit to a sexual encounter.
If the copulation were achieved without her informed consent, or through a trick, it was unwilling on her part. And unwilling sex is rape.
He by-passed her will in the matter of having a relationship with him, including a sexual one. He prevented her from fighting him off by lying to her, knowing fully that she would be unwilling unless he lied. It seems like rape to me.
A second point: The “'Til death do us part” statement in marriage ceremonies is not what you think. It is a declaration as to how long the parties intend the relationship to endure. Marriages are not for x years. The fact that their term is the life of the participants is what is being stated. If nothing else happens to alter their intentions, the marriage continues, no matter how many years go by. I think most people interpret it as you do, and I can’t prove my contention, but under this interpretation, divorce doesn’t reflect on the marriage vows so as to make the events of the marriage fraudulent.
A man who promises fidelity in order to persuade a woman to have sex with him, marry him, etc., must live up to that claim. I do think it is rape if he cheats. It is rape and more.