According to the majority of Muslim scholars including, Malik, Shafi’i and Aḥmad, marriage is regarded as invalid as long as it is concluded without the consent of a guardian (wali). AbūḤanīfah permitted such a contract. I think you made a mistake by concluding this marriage without the permission of her parents and this is the reason it brought up all ensuing problems. As long as you made the contract through a judge, it becomes valid even if according to those scholars who required wali as an indispensible part of the contract.

Divorcing her in writing is effective if you intend divorce. This is the view Abu Ḥanifah, Malik and Shafi’ī. Anyhow, even if have intended divorce, you have already revoked it later. Therefore, she is still your wife according to the advocate who knows regulations governing Islamic marriages in your country.

My personal advice is that you exert all possible efforts to talk to her family and try to please them and apologize for what happened. In this case you can regain her again since she is still your wife.