Relationship problems

I am 24 years old and in a 4 year relationship. I'm starting to get to the point where I'm realising that in reality I'm not happy with how everything is? I love my girlfriend but I have no real emotion and motivation for the relationship. We never had a strong start and at times I feel like I've kept this going just for the sake of ease and to not cause problems. This would be simple but we live in a rented place for the next year and if we broke up it would just cause such a mess and she'd have to stay living with me

For a few months now tbh. I just feel trapped and cut off from people and the relationship feels so flat