The phrase "is with you" can be substituted by various synonyms, depending on the context and the level of formality required. For instance, "accompanies you" conveys a sense of someone being present beside you, while "supports you" implies someone is providing emotional or practical aid. "Stands by you" highlights loyalty and solidarity when someone is going through a tough situation. Other options include "helping you", "being there for you", "assisting you", "standing with you", and "backing you up". Depending on the intended meaning and tone, selecting the appropriate synonym can enhance the clarity and impact of the message being conveyed.