I think u are suffering from anxiety ,depression ,too much mental pressure and these all are mixed up with ur relationship problems.
I think u have to evaluate some past history like ur childhood history,any long lasting mental grief,any abuse,history related any harrasment etc.
All these info help a psychologist to find a proper way to deal ur problems.Consult psychologist online or offline immediately .
Next Steps
I think u try to keep busy urself on work,and took ur mind away from ur partner.Concentarte on ur passion,hobbies,reading books,spent quality times with family and friend.
Give time to urself also.U evaluate ur ownself.It is also sometime give great help in wrong situations.
best wishes...