He's married since the 2nd of December...

[Allthewayanime]

Would it be correct to say: He's married since the 2nd of December instead of 'has been married'?

[Dozy]

"He's / He has been married since the 2nd of December" is understood to mean that he got married on December 2nd, and has remained in that state up until the present.

"He's / He has married since the 2nd of December" would mean that he got married on some unstated date after 2nd December. However, it feels rather awkward and unclear, and if you wanted that meaning it would be better to say it in another way, such as "He got married some time after the 2nd of December".

[Allthewayanime]

But if I would like to talk about his status as in : He is married since the 2nd of December, would it be correct?

[Dozy]

No, that does not sound right.