Love is the letting down of your defense system, so that, that which is Divinely presenting itself to you—even though it thinks it’s an ego and acts like an ego—can be seen and acknowledged by you, is what constitutes the act of love.
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Dear Members and Gurus!!

Is the above sentence grammatically correct?
What is the subject of "is what constitutes the act of love"?
It's difficult to figure the structure of this part.

( Don't put a comma after 'so that' ).

There is no proper subject for "is what constitutes the act of love", so the sentence is incorrect.

My feeling is the writer started to write without planning his sentence sufficiently beforehand. Em dashes often suggest that, too.

Thanks Clive, as always....