Crazy jealous

Hi! Me and my boyfriend have been together for a little over a year. I've never been a jealous person but with him, i go crazy over the smallest things! Even if a girl likes his pictures, or even if I see OLD comments/conversations from/with girls on his Instagram/facebook...etc. The thought of his ex's or girls he's "talked" to drive me up a wall. How do I get over this???? I know I am very insecure so please don't be rude. Ugh he's just so hot and sweet and perfect I just don't want him to find better. I know he's mine, and we live together! I'm just afraid my craziness will ruin us! I know he has to love me if he's put up with it this long lmao. But please, advice? How did you get over jealousy issues?