sometimes relationships shrival up, people don't feel the same any more. Distance can make the heart sad and people cope with it in all different ways. His way seems to suggest that he misses you. Because of the time apart from each other, everytime he hears from you by phone, he needs to have a big converstaion, he needs to hear laughter and compliments and big love. It needs to be addressed to him deeper than if you were face to face to show your love. You can't be with him to cuddle him physically so he needs a phone cuddle, he needs a good talk. Take a deep breath when you next speak to him, say what is on your mind, tell him about how you feel, that you feel un-able to speak to him about stuff because you don't know what to say, because it's been a long while since last speaking to you/seeing you,and that's why you find it hard to find the right words, or that you like him so much, it makes you tounge tied. Tell him that you don't wish to give up on him. He will want to hear it. Because a) you will be talking and having something to say, and b) he will see that you are opening up to him and he will appreciate that, it may even get you closer again.
On the other hand, if he doesn't feel the same way anymore, then you will have to accept that it's time to move on with 'your' life.
You can't live a life on egg shells not knowing what to do, or live your life in a dream of you both being how you used to be. Because people change and you may need to face this challenge.
There's two ways in life. Living with it or dealing with it.
And there's only one way to find out.
The best of luck to you anyway, give it ya best shot!
xxx H:Kevill xxx