Wanna go out with me? - Maybe or Probably.

Maybe is 'possibly'.
Probably is 'most likely'.

No maybe in this case is 'I am not sure yet, but there is a possibility'.
But in reality, when I girl says, 'maybe', then she does not ever want to go out with you !@@@@!!

incorrect

I wouldn't trust what he says. He doesn't seem to have a good grasp of English or interpersonal relationships.

Sounds great.
Though it might be rather difficult to get together for some time
as I go to work on Sundays as well, but it'd be so good to see you in person.

Hi,
Maybe indicate possibilty that she might go or not.
Probably indicates almost certainty.