Is it permissible to continue working in dream interpretation, knowing that I fear there may be a suspicion of its unlawfulness in this work, and some people who I interpret dreams for have become attached to me?

The knowledge of dream interpretation should only be undertaken by someone who possesses knowledge and expertise, because it is akin to issuing a fatwa. If you have knowledge, then there is no harm, and it is permissible to take payment for it. If you wish to abandon it, there is no harm, for it is not obligatory, and abandoning it might be closer to piety.