Atheist - someone who denies the existence of god
Irreligious - hostile or indifferent to religion
Indifferent - marked by a lack of interest (Just incase someone didnt know 
)
Religion - a strong belief in a supernatural power or powers that control human destiny
God - the supernatural being conceived as the perfect and omnipotent and omniscient originator and ruler of the universe
Thus, Religion - a strong belief in God. (From definitions 3 and 4)
Definitions courtesy google define: term searches
I would say you are kind of indifferent to it and you are clearly deniying gods existance in your explanation.
My answer would be
atheist mainly but you are also irreligious.
If you are an atheist, you deny the existance of god, thus you dont believe in religion. Religion is a "strong belief in God" and thus you dont believe in God. I belive this implies/could imply that you dont care about this matter ie you are indifferent to it. And thus you are irreligious.
Thus being an atheist implies that you are pretty much irreligious (in an indifferent manner and not the hostile one) but you cant make an implication in the opposite direction.
Your hostility (in the sense aggrevation), if restricted to the dumb things people do in the name of religion like
here then i wouldnt really consider that hostility.
Thus my answer is you are an atheist (and this implies you are irreligious as well i guess
)
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