What are some red flags to look for in relationships? ?

habitual cheating.

Incompatible sex drives.

Different values. Moral, political, philosophical, when it comes to having kids and child-rearing.

Different attitudes towards spending/saving.

Different dietary and lifestyle habits.

Being a functioning addict.

Constant lying, distrust, bad hygiene, jealousy, unfaithfulness, controlling behavior, & and rudeness.

Too much emphasis on self-gratification, self in general, or obsessions with hatred or envy.