My boyfriends bit the same but he says he doesn't want to get soppy on a text but when I see him doesn't get soppy then either. He hasn't even told me he loves me and we have been together 6 month. I think you should give him time he might be bit shy in expressing his feelings some boys are like that I suggest you egg him on to tell you how he fees like say have you missed me ? And see what he says that's what I do ha good luck!
Tell him how you feel about it when you are face to face with him. Chances are if this is a fairly new relationship,he is probably a little shy when you are face to face and finds it easier to express himself in text messages. Since you have already told him, I would try one more time and let him know that it hurts your feelings and how serious you are about it.
I think men are that way in a brand new relationship. It seems to take them a while to catch on. Your boyfriend sounds extremely shy. It is easier to say something if you aren't facing that someone. Give him time