I don't know how to help the situation anymore

My boyfriend and I have been together for 1 and a bit more now. I love him and I care for him so much but he's acting a bit odd. He seems like a different person sometimes, a little more reserved and quiet and.. bland..? I want someone who is engaging and is interested, someone who satisfies me and gives me attention. Sometimes he does and other times he doesn't and it breaks my heart because I feel like I deserve the right treatment. I also feel like he does not try to understand why I get upset with him sometimes and he has even tried to invalidate the way I felt before on something he said when I got offended. I don't know if I look too deep into our situation but i'm so tired of this. It makes me unhappy and I'm not sure how I can help this situation. Any advice?