1. No he cannot get divorce without approaching the Court.
2. Monthly maintenance is separate and the Divorce issue is separate. Even after divorce maintenance can be claimed. Divorce is usually granted after the trial. When two persons cannot live together it is not advisable to forcefully continue with the marriage. If your husband applies for divorce, after the trial he would be granted divorce as it is clear that marriage is not compatible and that you are not willing to stay with him.
3. Yes you can go and stay in his house but who is in possession and under whose custody the keys of the house are? You cannot forcefully break the law, you can apply to the court get accommodation even under Domestic Violence Act.
4. Cruelty includes mental torture. You can file case under 498A of IPC and the Police will investigate the matter and if proved he will be put behind bar.
5. Booking under Domestic Violence Case does not take away his job. But 498A under IPC yes he will lose job if he is government employee, if not depends on the private company management.
6. If you book case under 498A yes he is barred from leaving the country if applied to the court.
7. No one can harm anyone..there are provisions in law to get protection from Police
8. No he cant get married without divorce from court of law.
9. When you do not want to go back to him, mutual divorce is better so that matter may be settled in a short span of time. Litigation takes time and expenses involved. Ultimately the quantum of amount is dependent on evidence. In mutual, you can negotiate and arrive at one amount acceptable to you.