I actually do know of several women in the church who have adopted:
1. Served a mission in China, never married, went back in her thirties and adopted three kids. The kids are sealed to her father.
2. In her forties, never married, adopted a child in the US.
3. Husband died before they ever had kids, never remarried, adopted children from China, kids are sealed to her and her deceased husband.
4. In her thirties, a teacher, adopted one of her students.
In all circumstances, I have seen the wards be completely supportive and mostly non-judgmental. Yes, children should have the opportunity to have a father in their lives. On the other hand, in all of these adoptions, the children were taken from potentially damaging and negative circumstances and placed into a stable, well-educated home where the parent truly loves and wants them, and can provide for them monetarily, spiritually, and emotionally. I can't see that that is a bad thing.