Bf only loves me 70%???

So I just got off the phone with my boyfriend and it's like 3:43AM right now but I called him because I was overreacting and worried. Him and I have a kind of rocky relationship. We are getting to that point in our relationship where things get kind of hard. But there's a lot wrong with me. I overreact about a lot of things that I shouldn't overreact about and I know I do. And it got to the point where my own bf was afraid to hang out with me because I do that so much. I'm working on myself and I want to change myself. But today I asked him if he still loved me and he said "uh yeah" and I was like what do you mean? And he told me that he still loves me but kinda doesn't. This broke my heart. I didn't overreact about it though, I asked him why and stuff and he said he only loved me about 70% but he still does In fact love me. He hasn't said "i love you" to me in about 3 weeks and I always wait for him to say it to me first for me to say it back and he brought that up, how I never say it. He was kind of waiting for me to say it to see if I would say it first. He's going to China in about 1 week for 2 months. We have broken up before and I convinced him to give me another chance because I knew what I had to change about myself to make him happy and to make myself happier and a better person. Well, he just now told me that he doesn't know if he can give me his everything like he did before. I always wait for him to do stuff for me so then I can do stuff for him and I know that's not the way to be and I wonder if that's a factor. So what can I do? What should I do, before he leaves that will make him love me more? What can I do now that'll make him miss me when he's in China and realize he really really does want to be with me? What can I do while he's in China to make myself a better person so when he comes back, he will be surprised? Please help! I don't just want to do this for him but also for myself. He gives me motivation to want to be a better person. I know I can't force him to love me more and want to be with me and miss me but I can contribute, right? Please help! Any advice will be great!