How do I help my daughter who developed a phobia of going in

How do I help my daughter who developed a phobia of going in the shower over a year ago. There was a period when she was having panic attacks all the time and had a couple in the shower as well as OCD around the shower. She cleans herself with a washcloth but it is not ver effective and lacks poor hygiene now. She says she is afraid the OCD she will have in the shower could go on for hours. She does not have panic attacks any more but still has OCD. She is 20 and lives at home refuses to see a professional because she says they have only harmed her in the past. She refuses to consider medication.
What can I do to help her?

Try a bath, may need a bath chair also!

@rascal1
Thanks. But she has a phobia about the bathtub and shower.
Maybe if if could create a bathtub in the kitchen it would work but I don’t want to reinforce her avoidance.

She says professionals have only been harmful for her and she refuses to consider medication.

@Nancybl Well then I am at a loss, doesn’t sound like she is ready for help as of yet. Anyone else have ideas??