Should I be jelous of my girlfrind talk with her ex?

I have been dating my girlfrind for almost six mounths and she sill talk with her ex...here some of the info I have know her for 3 1/2 years and six mounths ago she broke up with her ex of 10 years for me but she sill talk to if and he tex 1 to 2 times a week...and like this week she had two family dinners and he was there but I was not invited and this morning he was joining the family church and her grandma wanted her up there granted alot of the family is in town for outher resone right know and they will be up there.....but like last night he tex her and ask if they cdould hang out somtime she never tex if back as far as i know ..but than about 11 pm he tex her to say good night ..but agine she told me aboute it...I understand that she want him to do good and all and the guy not a bad guy heck i hope he dose well to just not with my girl...so what the opinions here!!!!