F a Christian man or woman can live in celibacy (happily and holily): awesome! He or she can devote more time and energy to serving Christ than can a married Christian (vs. 32-33). However, most of us can't, or couldn't behave indefinitely as a single Christian. Attempts at it without God's grace and blessing will inevitably lead to sexual misconduct (vs. 7). Paul saw this and understood it. While he recommended celibacy, in order to avoid bad behavior Paul advised marriage for most (vs. 2). Of course, marriage is a good thing, ordained by God as the first human institution. God Himself said that it is not good for man to be alone.
Now, it is unmistakable that Paul charges every married believer to be a good spouse. Every husband belongs to his wife. Every wife belongs to her husband (vs. 3-5). Sexually, emotionally, spiritually, financially: in every way, God blesses unity and agreement within the bonds of holy matrimony. Separation and divorce are not part of God's will and plan (vs. 10-11). Are there exceptions? Sure. If an unbelieving spouse chooses to leave their believing partner, Paul clearly declares that the believing divorcee should feel no shame. They are not guilty and should feel no burden of guilt (vs. 12-13). Still, staying together even with an unregenerate spouse is good, if the unbeliever is content to stay. God's definition and standard for heterosexual monogamy in marriage is clear and unmistakable.