Is the woman considered sinful for repeatedly abstaining from engaging in intimate relations with her husband, and what is the solution to her problem?

It is not permissible for a woman to refuse her husband's bed without a legitimate Sharia-compliant excuse or significant harm. Rather, she must obey him if he calls her to bed. Jurists have considered her refusal without an excuse to be an act of disobedience (nushooz) and a major sin, due to the severe warnings mentioned in this regard, such as the angels cursing her if her husband spends the night angry with her, or the One in Heaven being displeased with her. As for crying and feeling distressed during intercourse, there is no sin in that, because it is something she does not control.