the answer you got jeden mi?o?? is garbage.
now, for the real answer, polish has two words for one, one of which means one and only, the other tends to suggest that there are others. moreover, we tend to say "MY one (and only) love". without the
"my", it sounds a bit strange to me (and i think to others too because when i did a web search, it keeps popping up with the pronoun). so the form i like is
moja jedyna mi?o?? "my one-and-only love"
i suggest before getting a tattoo, you check with a couple of other speakers of polish and make sure they agree.
