be less jealous

ok, there’s this girl that is dead set on marrying my boyfriend (she says that their parents have arranged for them to get married)... yeah, my thoughts exactly. it used to bother me a lot, but the other day i found out that she’s only 17 (just turned) and my boyfriend is 26 (27 this march) so she’s like 9 1/2 years younger than him. last night he told me that he’s starting to feel old b/c he used to be able to find girls that are 17-18 to be attractive but now he just sees tham as children. i know that doesn’t make me any less of a jealous person, but it makes me feel better to know that (maybe) he won’t go running off to her. (a little confidence will hopefully make me less jealous)

everytime i think of him cheating on me i feel so foolish, if he does it will be my own fault. it isn’t that i dont trust him, its that i dont trust other women. i was never like this before, but it seems like everyone close to me has left me and he is all i have left here(my family lives far far away) and i dont want to lose him too. any advice?