Question: is gimli the only dwarf left?
Answer: No, Gimli was not the last of his kind: the Dwarves of Erebor (the kingdom refounded after the events of The Hobbit) still existed, and Gimli does return to his people after the War of the Ring. ... After the fall of Sauron, Gimli brought south a part of the Dwarf-folk of Erebor, and he became Lord of the Glittering Caves.