[Many years ago I stopped giving advice that nobody wants to hear; now, instead, here is some advice that somebody wants to hear.]
The only thing that is surprising (to me) about this story [that you've sent in to me] is the question that comes at the end of it:
"What would you recommend so I stop obsessing over this person?"
It is surprising to me that this is the question, that this is the problem you're struggling with.
Note that I do not identify as an egomaniac, but my own lack-of-egoic-weakness (shall we say) is part of the equation here, and will need to be mentioned.
Do you actually feel that you're better than him? Do you actually feel that you're "too good" for him?
Maybe the answer is no: maybe you feel that he isn't inferior to you, that he isn't contemptible to you, that (really) you wish he would love you (and that you could love him), etc., because you do not regard him as inferior at all.
I think you would admit that if you regarded him as entirely inferior and contemptible you would not be struggling with these feelings.
What do you need to do —in your own life— so that you can feel that you really are (starkly, absolutely) "too good" for this man?
Let me use Hitomi Mochizuki as an example here (a quick "google images" search with that name will familiarize you with why I'm using the example).
What if Hitomi Mochizuki wanted to fuck me? How would I feel? I would feel contempt toward her: I would feel that I'm too good for her. Again: I do not identify as an egomaniac. The basis for this feeling of contempt is not my physical appearance, nor hers: as far I know, Hitomi has worked as a professional model to some extent, and she is regarded as extremely beautiful by a huge percentage of people (she's not everybody's type, she isn't sexually appealing to everyone, but nevertheless… she's the object of desire for many, perhaps millions, of men and women).
If I went through a similar scenario (as you went through with this German guy) with Hitomi lying to me, or with some other attractive woman with similar attitudes (at a similar level of ignorance and stupidity, etc.) lying to me, how do you suppose I would feel if the lies were revealed (after we'd been arranging to meet but) before we'd met?
I would feel contempt for her, right? I would regard her as despicable. I would feel that she wasn't worth missing: she wasn't worth having regrets about, she wasn't worth worrying about. Even if I actually had met and fucked her, I would feel that she wasn't worth fucking: I would regard her as someone who wasn't worth falling in love with, I would feel that she wasn't worth having any kind of "reasonably profound" relationship with.
If I had never lived the life of the mind, in the same scenario with Hitomi, how would I feel? If I hadn't read a single book since the end of high school, how would I feel about a flirtation with such a woman, or a relationship with such a woman: if we're both merely living "the life of the body" and not "the life of the mind"? Comparing body to body, I'm her inferior; comparing the whole person to the whole person, she's utterly contemptible to me —she's beneath me.
Now ask yourself: why is it that you do not feel this way in relation to this German guy?
He's a bad person in various ways that you've described, but that's not how you feel about him: you don't feel contempt toward him, you don't feel disgust, you don't feel that you're too good for him (that you're too good "for this", in general).
Why?
What would you need to do (with your life, with "the life of the mind", etc.) to feel this way?
