a)if two things go together, they exist together or are connected in some way 同时存在,相伴而生
Alcohol abuse and eating disorders often go together.
酗酒往往伴随着饮食紊乱。
nGrammar
In this meaning, go together is not used in the progressive. You say:
The problems go together.
✗Don’t say: The problems are going together.
b)RELATIONSHIP old-fashioned if two people are going together, they are having a romanticrelationship 恋爱
Examples from the Corpus
go together• Brainsize and cleverness do not go together.• They decided to go together, by their thousands, to the place where they were told he could be found.• It goes together easily with butternut squash, onion, potato, carrots and broth.• Those two words go together for owner and worker alike.• Geopolitics and gratitude do not go together, it seems.• The problem is how those things all go together to form one highly organised complicated thing.• Community and confrontation don't go together, which is fair enough but a bitcosy.