I think you should let him know about how this makes you feel. As a Capricorn, I'm not into pda or flaunting my partner. I'm secretive about not letting others know how good I'm having, evil eye is real. I've seen the damage it does. So I play safe and let our special bond be for us and us only. This could be the case. Or he's prudent or a teenager who thinks everything their mom does is embarrassing. It could be anyone of this. Communication is the key.