I think that if this person is has messed you about ( i presume this is about yourself) as in ignoring you then ignore it once, after that if it continues you should consider whether it is working and primarily whether he actually cares about you as much as he should. If he is ignoring you a lot then maybe he does not see your relationship as serious, if this is the case you need to talk to him, he may also not realise that he is doing it and you need to bring it to his attention. After that if he continues to mess you about then you may need to end it; if you ignore it it may get worse and it's only you who will be getting hurt.
so to summarise; talk to him so he knows how you feel and see how it goes from there. Just think, is this what you want and is he good enough for you? Noone deserves to be messed about.
xxx