I'm sorry but i don't find this destructive, i find it to be normal behavior of an 8 month old baby.

I have 4 children and they all went through it. my oldest is now 8 and loves to be with his daddy. Assure your husband that this will pass. Maybe not now, maybe not in a week or a month but as long as he is involved in his life and continues to show him love and affection, he will reap the benefits, even if its not for a little while. Your son is a baby, he will be 8 in a blink of an eye. don't worry yourself about this, please. Love him and continue to build his trust in you as a safe place and he will get past his dependency. For now just wallow in the old saying that no one is better than mommy!