I'm jealous of my multiple personality adopted brother monopolizing my boyfriend's time and attention.
Why would you think like that? Are they spending a lot of time together?
Yes, and that is time my boyfriend should be spending with me.
Being jealous of people isn't healthy. You should be glad they get along so well.
I love my boyfriend so it's not fair that he should spend time with other people.
Your boyfriend needs to have friends too. Spending too much time together will cause problems in the relationship. It is wrong to be jealous of someone else when you know that he cares about you.