Understanding jealous feelings and behaviors in your boyfriend helps you watch out for yourself. Jealousy may be present in a man when he. Signs to look out for in a relationship to save yourself from an overly jealous guy! - 10 signs of a jealous and possessive boyfriend!. How do you know if your boyfriend is a little bit too jealous and controlling? Here are 10 signs he's too jealous and possessive even if you think.