Agreed, Ben, though not with as much emotional appeal.
There are people who aspire to be as noble, idealistic, and strong as possible, and there are people who believe we are physically deterministic animal and will go to great pains to show that flaws are not only acceptable but "humanizing."
Both points of view have certain arguments, premises, etc. that are arguable and or fallible. I suppose the question that arises is which would you prefer to be? Personally speaking, the saving grace of humanity is that it can aspire to be greater in both act and intent than animals. Perhaps you don't believe that. It's your right not to believe that, but would you argue it's a noble one to excercise? And if you do not believe in nobility, then what precisely distinguishes you from your average animal aside from the material trappings?
Which pushes me to examine the remark "I am human." What does it mean, exactly? I suppose it means "I'm fallible," if one speculates upon the author's mindset. But its intent is almost classic in its absolute vagueness, giving it a distinctly sophistic quality. It means nothing to say I am human, unless we take it literally to mean, "I participate in the species homo sapiens."
So all we know is that she identifies what kind of organism she is, though the implications are loaded. To err is human one might say. But this particular person seeks to err. She (writes that she) enjoys it, justifies it, comes up with flawed arguments involving gender parallelism and psychological assumptive leaps, etc.
And yet she finishes with a classic waffle. "I am human." Ay, it's easy to say you are of a certain species. But what kind of human are you? After all, being a human being is hardly your choice. What kind of human being you are is your choice. Unless you believe you are governed by determinism and biology, which makes you no different from the average animal (at least from what we might scientifically know). If this seems like a one-or-the-other opposition, it is, because the concept of "partial determinism" is incoherent.
So if you believe in the former, if you believe in humans being better for being noble and strong, then you don't form a distinctly human agreement (in its reasoned origins and ideals) of monogamy and then violate it. Then, as Ben as so forcefully said, you are weak and selfish, or, for those biological determinists: a mere animal. So "I'm human" doesn't cut it. If you believe in the possibility for humans to be noble and strong, you say, "I'm an ignoble and weak human." If you don't believe in that, just say, "I'm a homo sapiens and no better than an animal, just like you." Just don't be surprised when decent people of the opposite sex seem to elude you, or when the person whom you think you are fooling turns out to also be fooling you.