"Soul-subduing" is a powerful phrase that denotes something that takes away your vitality and energy. It could be despair, pain, or any other negative experiences that leave you feeling drained. If you want to describe something that has the same effect, you could use synonyms like "demoralizing," "depressing," "dispiriting," "heartbreaking," or "devastating." Each of these words carries a weight of their own, reflecting their specific nuances. For instance, "devastating" suggests something that is overwhelming and causes catastrophic destruction, while "dispiriting" connotes a feeling of discouragement. Using varied synonyms that capture the same essence effectively conveys your message and brings depth to your writing.