Not letting me be there for him

My bf’s grandfather passed away and Friday was the viewing and Saturday was the funeral. I asked about the details and my bf told me that he’d rather I come over after the funeral at 3. I thought it was kinda weird that he didn’t want me there with him but I brushed it off and hung out with my sister.

I get over there yesterday and he wanted to get ice cream. Didn’t say anything to me about his dinner plans until I got there. So I was only good for two hours and then he had dinner. He made the excuse that he needed to be there for his mom but doesn’t let me be there for them.

I feel like as his partner I owe his mom my condolences but yet he didn’t want me there. I’m kinda afraid his family will think poorly because I wasn’t there yet he didn’t let me. I sure hope if I had a family death, he’d be by my side.

Is this weird or just his way of grieving?