I feel so annoying and confused...

My husband is not a big conversationalist. It takes a bit of adjustment if you are, but you get used to it. As long as you talk about the important stuff in life you will be good.  We will just sit together and be content in each others presence. He is also not one to text back all of the time, but I did tell him an I love you, a goodnight or good morning require a response. So now I get them if we happen to be apart for a night or two. So talk to him, that is the only way you will fix the issue. 

Have you told him it upsets you when he reads but doesn't respond? Honestly I do it sometimes on accident. I plan to respond in a bit because I'm busy, and then never do. But if someone told me how much that hurt them id try much harder to avoid it. As for the conversation lulls, those happen. It's okay sometimes. Just relax and enjoy each other's presence. 

If it hurts you, just tell him, "it hurts my feelings when you read my tests and don't respond" a relationship is only as good as its communication. I know you say that you don't mind that he's not a conversationalist, but at the same time, you want him to be. You can't one minute tell him it's ok if he doesn't like talking then the next be upset because he wasn't talking to you. You have to be very honest with your needs in order for them to be met. Good luck lady! Just talk to him about it.