If there is not one, use union organizational skills to get one started. Lobby federal, state and local governments for increased funding for shelters. Call your local shelter and ask how the union can help. Money is always scarce, so individual or union donations will be appreciated. Non-monetary contributions such as clothes or toiletries may also be needed.
Most communities have a hotline.
The union might provide volunteers to answer the hotline a few hours per month. Help women become more confident by running assertiveness training workshops. Include information about domestic violence as part of your steward training. Encourage, but don't pressure her to talk about the abuse. Respect her need for confidentiality.