Meaning of なのにだなんて

Question

　怖くなって体が動いてた 怖がってるくせにどこかでともえは俺のなのにだなんて勝手な事を考えてる自分もいて

What exactly is のなのにだなんて here?

なんて should be the quote but I'm confused by the use of 俺のなのに

ともえ is this dude girlfriend from context.

Answer 1

Your excerpt has no punctuations at all. Is this from a manga? A version with punctuations would be:

怖がってるくせに、どこかで「ともえは俺のなのに」だなんて、勝手な事を考えてる自分もいて。
Despite being scared, there's (a part of) me that thinks something selfish such as "Tomoe is mine but ..."

• 俺の is "mine" just as 彼女の is "hers" and 田中さんの is "Tanaka's (one)".
• Xなのに is "although (it) is X".
  • な is the attributive form of the copula.
  • のに is "but".
• だなんて is だ + なんて, but they are often used together. This だ is a special だ that adds a sense of disagreement or suspicion. なんて by itself is not a quote, but it sometimes works as a quotation marker that also expresses surprise or contempt.
  • Is there really any difference between だなんて and なんて?
  • What does だなんて mean?
  • だ in 「別に迷惑だなんて」
  • ~たいだとか why is there a だ here?
  • Is 「３人いるだと」 grammatical?