My boys are jealous of my bf, but not aggressive... they will not let us lay next to each other, they need to lay between us... if we kiss or hug they will jump on our legs (if we are standing) or in our lap (if we are sitting) and whine/bark at us. Over time they have gotten MUCH better. My boyfriend takes them out every morning which is their favorite thing, and he gives them treats. They really have gotten much better but it takes time, it won't happen in a week or even a month... just keep at it and he'll eventually change his mind!
Good Luck!