you are not normal if u dont get jealous don't blame urself.If he (ex/bf) doesn't respect ur feelings he is st*pid.Communicating with ex without having a deep reason is unacceptable "unless" they have kids.And if he still chatting to his ex online or through txt , facebook or watever the hell it is talking rubbish , flirting to each other are foul. If he really loves you he will respect you and never hurt ur feelings.

cheer up girl , and god bless you.

Move Forward thou it's not easy to do.