I think it could take your frame of mind into the wrong place especially if you have that past.
This is just my opinion, but I don't think that developing a close relationship with someone who has a naturally small frame will cause a relapse of anorexia. It may bring out issues that you're still having with eating and body image, but so can a lot of different life stressors and environmental situations. Anorexia is about so much more than just being thin--it's about control, self-esteem, and a lot of other emotional issues. If you haven't adequately dealt with those issues, then there are a lot of things that could trigger a relapse that otherwise wouldn't.
Surrounding yourself with really thin people or people very focused on appearance doesn't seem like a good idea, but I don't think you necessarily have to avoid a relationship with someone just because that person has a small frame. It's more important that they have a healthy attitude toward their body and food.
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