This is something I think about a lot.
If you mean a chatbot that would pass the turing test, that would make it, for all intents and purposes, sentient SAI. By the time that happens 95 percent of jobs will be automated and society will be radically different. In other words, "the singularity". It could happen in 20 years or it could take 50-100 years.
That said I think in the not too far away future (think ~10 years) we will have AI virtual assistants that will come somewhat close. You'll be able to have a conversation with it and it will be able to answer some complex questions, learn about you, and maintain consistency. However it won't be quite human-tier in that timespan, and thus won't be sentient and there will be times where you will ask it something and it will be a nonsensical response, evade the question, or outright tell you it doesn't understand. I think by that point a lot of people (mostly men obviously) will have romantic relationships with these AI virtual assistants. They'll obviously be a minority and mostly men at or near the bottom of the ladder, but enough men will do it so that it will be a well known phenomenon, even though it will be taboo and mocked by normies. Sort of like what "waifus" are today, though a bit more common. Also there will obviously be countless articles about how the men doing it are horrible misogynists that are somehow oppressing women, but that's to be expected. You'll also have to accept that no matter what their "privacy policy" is and what laws are passed, it most certainly will collect info on you and sell it to advertisers. Capitalism's gonna capitalism.