Can I file for divorce without my ex knowing where I live?

You need to commence court proceedings. To start the case, you need to personally serve the husband. You may apply to the court to obtain an order permitting you to serve by way of alternate or substitution service. To obtain this relief, you must show the court that you have made diligent efforts to attempt to locate him and are unable to effect personal service. You would complete an Affidavit as to the last known whereabouts of the husband and any information of his whereabouts. The possible methods of substitutional service are that you may serve a contact or relative of his, or you may take out a newspaper article. You need to speak with a family law lawyer to address the issue of service of the court documents. If necessary, which it may be here, you may also want to make a claim for a restraining order. You will also need to speak with a family law lawyer about the implications of addressing child support before the court would grant a divorce order. If you were to use an address for purposes of contact rather than your home personal address, or a lawyer address that may address your concerns about personal safety.