i always find that confusing about english. i suspect it's not just words but also a cultural thing, to an extent. in my language, there's no translation for the word "dating" (the act of going out together with someone). afaik people just describe their situation with the newly-met person on a case-by-case basis instead. like "i met so-and-so at a party" or "we watched a movie" and so on. and when people are in a relationship with each other, there's a verb for it, which would be as if you turned the word boyfriend or girlfriend into a verb (but gender-neutral instead), so it's very clear. truth be told though, i have no idea how people usually meet and go from being strangers to "in a relationship" where i live
back to your original question. the odd thing is, the way i understand it, "dating" and "dating someone" are actually different meanings of the word. so there's the meaning of "going on dates", which may or may not imply a relationship, and then when there's a name attached to it (dating so-and-so), it actually does imply a relationship with some level of commitment or emotional attachment, but not necessarily the act of going out on dates with that person. yeah, it is confusing... i guess different people have different ideas about those words, because they're not clear, and relationships in general are unclear nowadays. then when they really want to be clear, they use awkward makeshift verbs instead, like "being in a relationship with someone"