Sex can't solve any problem, only dialogue and understanding can. Sex may make couples fail to address some issues that they should have addressed once and for all, that doesn't mean that the issue has been solved. The sad thing about failing to address the issues that occurs in a relationship is that such issues would keep accumulating and the hurt, misunderstanding and resentment that such an issue is generating in the relationship will always be there until the issue is addressed and both partners reaches an understanding.

Sex may make a partner forget or fail to address a problem in the relationship when it should be address. But such act is not healthy for the relationship because such problem may likely come up again in the nearest future. Don't use sex to cover up issues that require attention in your relationship. It would put your relationship under intense pressure