Helping big sister with mental health and we're pretty close

I’m 22 M and my older sister (24F) has been struggling with anxiety and depression. We were always close growing up but we’ve become extremely close again these past couple years. Our parents think it’s great and are happy we spend so much time together. She’s getting professional help too.

She says physical affection really helps her — long hugs, cuddling on the couch, leaning on me, etc. It calms her down and makes her feel less lonely. We’re very physically affectionate now and sometimes people even mistake us for a couple when we’re out.

I love being able to comfort her like this and it clearly helps her, but I sometimes wonder if we’re too close.

Has anyone else been this close with a sibling while supporting them through mental health stuff? Is this normal/healthy or should I be creating more space?