Nothing is necessarily wrong with you; it's not wrong to grieve when someone we love is taken from us. Jesus wept at the tomb of His friend Lazarus, although He knew Lazarus would be brought back to life (see John 11:35).
After all, God in His goodness gave you and your husband many years together -- and He did so because He knew you needed each other. At one time, you were two separate individuals, but when you became husband and wife, you were united together and became one. But now that he's been taken from you, that oneness has been broken, and a hole remains in your heart that will never be completely filled. Something would be wrong if you didn't grieve! When a loved one dies we grieve, but when we believe in Christ, the Bible says, we do not "grieve like the rest of mankind, who have no hope" (1 Thessalonians 4:13).
At the same time, thank God every day for the years you had together. Thank Him, too, for the confidence you have that your husband is now in heaven, and completely free from the pain that gripped him down here.
In addition, be a friend to someone who has also lost a loved one, perhaps someone in your church. Not only will you help them, but you will also be helped. Most of all, keep your eyes on Christ and the promises of His Word. In time, your grief will fade. The Bible says, "Weeping may stay for the night, but rejoicing comes in the morning" (Psalm 30:5).