"Du Kang is the only solution" is a famous saying of ancient China, which comes from Cao Cao's A Short Song. This famous saying is usually used to describe that when people are faced with difficulties and worries, they hope to relieve their mood by drinking alcohol.
However, it can also be interpreted as an expression of love that "Du Kang is the only one who can solve the worries". In this explanation, "how to solve worries" means that people hope to find someone to talk to and rely on when facing emotional troubles. "Only Du Kang" means that this person's existence is like Dukang wine, which can make people forget their troubles and feel comforted and satisfied.