I am struggling to understand the definition of despise – which the OP suggests is the chiyuv of every Yid to feel towards someone with SSA. Does this mean to viciously attack them, as in violence, or to experience nausea in their presence? Does it mean to not converse with them, ignore them, not agree to work in their proximity, to deny doing business with them, rejecting them at a checkout counter? In the case of avoda zarah, the posuk tells us to shatter them and break their matzeivos (on entry to Eretz Yisroel which was previously inhabited by idolatrous people). If there is such a pronouncement in Torah for SSA’s, mechalelei Shabbos, or other baalei aveiroh, please cite a reference.
I suggest that one can have the casual connections and interactions with them as with any other stranger, without encouraging, endorsing, or supporting their “to’eivoh”.
So what is basic Torah hashkafah? It is certainly not based on my personal feelings. It based on what the Torah guides us to do.