Which is the deeper form of forgiving: being respectful of the offending person or trying to love that person?

If by the term love you mean willing the good of that person and then acting on this even when it is painful for you to do so, then love in this sense is much deeper than respect.  Respect is highly valued, but it does not cost the forgiver as much struggle and even pain as love in this sense does.  You can be respectful from a distance.  Love in service to others requires you to enter into that other person’s life to be of help, in this case to aid in leading a better life.