My marriage is ending and need advice?

it feels we have nothing in common anymore at all, the fun has gone, i dont even want to have with him, i do love him no reason at all to hate him or dislike him but just no spark, he is great with our 2 year old son they could no live without each other he is the best father ever, we still go out for the day and we have fun around our son but once he has gone to bed there is just no fun, we have talked about this and tried different things instead of just watching tv but ends up just the same, we have about once a month which i know is really bad but i only do it then because i feel i should do, i know it is bad and its got to breaking point, we talked about and different things and i feel i cant relax because of the house were in, we were happy till our loud neighbours moved next door and that got on top of me worrying about them waking our son i still do and i went unhappy from there, we decided we would move after christmas but now i am not sure what i want at all, i feel so guilty and i wnat him to be happy, i would work at it i wouldnt just walk away i couldnt, he is the best husband anyone could have and father but ually i feel nothing at all, not sure if it would just be with him as i wouldnt know so not sure if there is a problem with me or not? has anyone else felt this way or do you know where we could get marriage help, i need to do this for our family and i now understand its is not normal