Do I keep perusing..?

so I've been seeing this guy for a couple months, we do everything that a couple does. but the only thing is, he never answers my messages and we only hang out like once every 2 weeks. he's still hung up on his ex that he broke up with a year ago... (and it makes me kinda sad tbh). I'm here, why not live in the present?.. so my question is, do I keep Pursuing this guy? and if so.. how long do I give him to get over his ex and make this official? I'm not gonna wait around forever. I want a relationship. a real relationship.