What's the difference between these two sentences in meaning?
I can't believe I'm meeting you at last.
vs.
I can't believe I meet you at last.
Thank you for your answers
The difference is that one is incorrect.
I can't believe I'm meeting you at last. - CORRECT
I can't believe I meet you at last. - INCORRECT
The latter should be:
I can't believe I met you at last.
"Meeting" is the present tense of "meet". You would use "meeting" only at the moment of meeting someone. As soon as you have met someone, that encounter is in the past so you would use "met".
It is worth mentioning that "meeting" can be used different ways. It can refer to a first encounter with someone, but it can also refer to an arrangement to meet for a specified or unspecified length of time. A first encounter with someone is arguably over in a moment, whereas an arranged meeting such as to discuss something will last as long as two or more people are together. This will affect which tense you should use.
