I am just wondering about this question. It obviously does not add nor detract anything from their philosophy if they were or were not virgins. But I am just curious. I know that neither Nietzsche nor Spinoza were married. In fact, I know more, Nietzsche condemned marriage as an option to philosophers. So not only Nietzsche was not married he was against marriage altogether for anyone who wishes to practice philosophy.
I hardly know anything about Spinoza's social life. He was a lonely philosopher. You need to consider that he proceeded the Enlightenment, he was essentially all alone when he wrote his works. He was cast out of the Jewish world and never seemed to intermingle with anyone else. Maybe I am wrong here. But I really have a tough time imaging Spinoza being with a girl (or a boy, but I doubt he was gay). It is quite possible that Spinoza was entirely asexual and so did not care about this at all.
Nietzsche definitely was not asexual. He did like women, very much. But I doubt he ever had sex with one. People often say that he died from syphilis that he contracted when he was younger and a bit more normal, but that is just a legend. In 1889 he was sent to an insane asylum where he remained until death in 1900. If you are interested to see Nietzsche on video in an insane asylum go here. His insanity was the result of some brain disease. People blame it on syphilis but from what I read syphilis does not match up with his symptoms. Nietzsche's father died from a brain condition also, so it is more likely to suggest that Nietzsche suffered from a brain disease he got genetically from his father. Nietzsche was a very sick man his entire life. A better explanation for the diseases that he picked up in his life is rather that he got them as working as a medical driver in a wagon, in those days there were not a lot of medical safety standards. But Nietzsche never seemed to have any success with women. Walter Kaufmann, the biographer of Nietzsche, said that women were scared off by Nietzsche's looks. There is no historical evidence of Nietzsche ever being involved with another woman. Nietzsche was also a lonely person in his life and did not interact much. He did have a few "friends" including Freud and Wagner, though Nietzsche became an enemy of Wagner when it became apparent Wagner was a nationalist and an anti-semite. From his insanity, personality, and his hideous looks alone I possibly cannot see him being with a woman.