Thank you for your questions.
The husband is religiously obliged to fulfill the sexual needs of his wife, and must do so every so often, otherwise he would be sinful.
Some scholars say once every 4 days, some says at least once a month and others says atleast once every 4 months.
Your right, scholars don’t provide a balanced message.
One reason is; men have a stronger physical need and women have more of an emotional need.
And it’s not very common for a man to refuse his wife. If he does, there will certainly be an underlying issue.
A wife must refuse sexual intercourse if she is having menstrual/post-natal bleeding.
Or she can refuse if she is genuinely really ill, in which case the husband should be reasonable and have control, or she can fulfill his needs in other ways, if she is not well enough for intercourse.
Hope that helps.