Most Helpful Guy
Like you said, he doesn't know what he's doing.. i wouldn't worry about the messages but the best thing to do is probably to get him alone and really ask whats up, it has to come from 2 ways or it just won't work, and there might be a chance that he doesn't even realize what he is doing wrong. Communication is key, that probably counts double for a introvert or a shy person
Most Helpful Girl
Try and engage or let him know how you feel. Tell him what you want to do about it so you'll both compromise. Or he could be cheating at the same time. If he doesn't change all in all he's just a boring person and those types of people suck.