The family occupies the front rows of the church (or venue).
For a formal, traditional funeral it would be:
Widow/widower, parents and siblings (with spouses) of the deceased first. Then children of the deceased, with their spouses, children, and grandchildren, each family together. Nieces, nephews, aunts, uncles, and cousins of the deceased would be beyond that. If a child or grandchild of the deceased is not married but has a close romantic partner, that partner sits with them. If the family is large, this can be quite a production.
OP, during funerals, spouses are always expected to sit together, both to show a sign of family solidarity, and to privately give one another support. So your instincts are correct, you would sit with your husband.