What fulfills the requirement of Suhoor?

Suhoor is fulfilled by eating even a single date or drinking a sip of water, anytime after midnight and before Fajr, with the intention of strengthening oneself for fasting.

Does using a wet miswak while fasting break the fast?

Is a wife considered divorced if her husband refused to go to bed with her (for sexual intercourse) for two months?

A wife doesn`t get divorced no matter for how long her husband refuses to have sex with her, and she had better go to court.

Is vomit among the nullifiers of Wudu (ablution)?

Vomit does not nullify Wudu, but it is a Najaasah (impurity) that requires rinsing the mouth and washing whatever became dirty by it since the prayer becomes valid only after the removal of Najaasah. And Allah Knows Best.