major trust issues?

my husband is going back to school to get his AA, and i dont want him to at all, why? because i just know it that hes gonna see someone he finds more attractive than me, possibly falls in love w her, no longer see me attractive. and possibly cheat on me. idk if hes ever cheated on me or not, but he has cheated on his ex wife when she was pregnant. he told the woman he fell in love w her @ 1st sight and fell out of love w his wife. asking her for sex. saying its normal to fall out of love and in love w someone else while in a long relationship. sigh, idk, i feel like this is gonna happen to me next when he goes to school. hes gonna find and get involved w so many young, pretty girls. what should i do?