Should my husband keep searching for feelings he thinks he should have about feeling connected to his mother who died 2 yrs ago?

My husband and his mother were very close. He always believed that when she died he would be devastated.  She'd gone through a lot over the past 15 years, including suicide attempts, depression, and strokes. Because of this and my husband's practical way of thinking, he knew that he would be somewhat "prepared" for when she died, but again thought he'd be left missing her a great deal. She died about 2 years ago after suffering for a long time from effects left after a stroke.  He told me last night, while he does have days where he thinks about her, he's troubled by the fact that he doesn't and never did have the intense sense of loss he always thought he would. He is also troubled by not feeling any connection with her on a spiritual level. While he's not religious, he never thought the connection b/w them would just disappear. He doesn't want to see anyone about these feelings.  I was just wondering if you had some advice I could pass along to him to help him with this absence of feeling. I just want him to be at peace, and so would his mother.