I have two things to say on the subject, neither of which are immidiate feel good things:
first, consider how you would feel if he were to be with you and texting to her all the time. A simple hello is the means to start a conversation. This brings me to my second opinion, tell him how you feel. Conversate, talk these things out. Tell him you'd like to know you're still a part of his world when he's not around.
if all you need is a "hello, how are you my love?" LET HIM KNOW. Most of the time, merely asking for what you want will be rewarded.