Communication is the key to most things, and especially to successful relationships. Being able to talk things through will strengthen every relationship you have. It isn't easy, but it's very worthwhile to learn how to effectively communicate.
Communication has four parts (or five, depending on who you ask): what you say, what he hears, what he says, and what you hear (and the fifth part, which sometimes applies, is what outside people hear or overhear). Sometimes, when we talk to someone, we're actually talking AT them. We're not verifying if they've actually heard what we've said. Sometimes, people hear your words, but don't understand them or misunderstand them. By working on all four parts of communication, you can make sure that the important things you're saying are actually being heard on his end (and vice versa, by the way).
There isn't enough information here for me to give you a really in depth answer. If he is a good person and there is no abuse going on, if he has not given you any indications of cheating or infidelity (talking to other females is not necessarily an indication of anything other than ... talking), then spending the time to learn better communication skills together would be of huge benefit to you. As always, if abuse is present, please do walk away.