As a 50% owner you cannot be forced to sign. Without a lawsuit all the selling half owner can do is sell his 50%, placing a messy almost unmarketable title. There is a lawsuit available for multiple owners who cannot agree on what to do with property called an action for partition and sale. A court can order the property sold and the various owners paid their share if he determines that it is in the best interest to do so. Your signature is not necessary. The judge’s order controls. However, that kind of court action takes about a year, is expensive and the court may determine that the best thing to do is not sell it.
Get a divorce lawyer immediately. this is not just a question of who put what into the home. Your husband may have an obligation to support you. Check these pages for find a lawyer- for family law in your area. Or look through Martindale for an AV rated lawyer in your area.
The court may require your participation if the property is ordered sold or to your husband in a dissolution. If you don't comply, the property may be sold at auction.
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