My boyfriend is acting so different please help

So my boyfriend and I have been dating for almost two years and he lost his dad last August and now it’s coming up to one year of his dad’s passing and lately he’s been so distant and not really wanting to let me in on how’s he’s feeling I feel as though I am doing something wrong and I ask him and he’s always avoiding what I ask. I just feel that we are growing apart and maybe it’s something else other than his dad but I could be just over analyzing it all. I told him if he needs a break or he no longer has time for me I understand. He’s always saying he never has time to spend with his family and do the things that he wants to do. I feel as though I’m a burden. But he always says he loves me and he want to get married. Idk am I going crazy?