Reality, or male fantasy? - Sex in the novel

Tricky thing for a novelist - sex scenes - how to depict, what to depict, how to use sex as part of plot and of character development as opposed to cheap thrills or a a force that overwhelms other elements of the novel. I have joked a few times, when reading from Exiles, that the main character and his experiences are based closely on mine, except that he had a lot more sex. True - so why did I have "add" sex to the raw ingredients of memory and experience? I tried as best I could to have the sexual relationships the protagonist engaged in be relevant to the plot, to his development of personality, his movement from innocence to experience. Also tried to have them be credible as much as possible - not the sudden passion random encounters that occur in literature (and film) and rarely if ever in life. Still, I know that some readers (my co-workers) noted exactly at what page the first sex scene began; others raised the issue of too much sex (I accept that criticism and welcome it - with flaws like that...). Reading Andre Aciman's memoir-like novel, Harvard Square, I go over these thoughts and issues again: the main character may or may not be based on his experience, and his experience may or may not have included attractive young women more or less flinging themselves upon him, but whatever his experience may or may not have been his use of and depiction of sex in HSq makes me raise my eyebrows - really? - these sexual episodes seem a lot more like a male fantasy of youthful abandon, or, more accurately, of female submission, than of anything approaching real depiction of how young people act, feel, behave. Granted, the novel is very much about the awakening of the unnamed narrator, guided by his Id-driver alter ego Virgil, Kalaj, but the novel is in danger of devolving into a catalog of scores. As noted in earlier posts, Aciman much stronger on description and, to a degree, on character than on plot - more than half-way through and there's no obvious plot element to keep me engaged. But there are occasional wonderful passages, such as his brief description (p. 131) of why he sometimes thinks in French (his native tongue).