My friend Lana is disabled in her legs, result of the accident when she was 14. So she's in a wheelchair. She also has movement issues in the rest of her body.
We've known each other for a few years now, we met at the university and now we're both in grad school. I was her first real friend in her life as she puts it, as others have never been interested in friendship with her. As months and years went by we became closer, we did a lot of things together, we studied together and we were great friends. Her family are rather protective of her but they trust me completely with her.
I never looked at her sexually, she was more like a sister to me. I never considered dating her either. I really love spending time with her and being her best friend, the one that she trusts and can always rely on.
Yesterday we submitted a major piece of coursework and we're finally free. I asked if she likes to celebrate. I picked her up and brought her to my place, we ordered pizza and had a few beers and enjoyed ourselves. The plan usually is that she takes my couch these nights as she often stays here (a lot of the times it's studying together though).
Last night she was really intimate and kept holding my hand. One thing led to another, we were having sex on my bed. The sex was very good, but that level of intimacy with her was amazing, like something I had never experienced before in my life. After sex she laid on top of me and told me that this was her first time having sex and she's glad that it was with the right person. We slept in each other's arms. This morning I drove her home and when we arrived she kissed me and told me that she's glad that last night finally happened.
I'm a little overwhelmed. On one hand I certainly love her and last night felt very right when it was happening, on the other hand I can't shake off this feeling of guilt that I'm having right now. I feel like she's been more or less isolated in her life because of her physical condition and I'm the first person who's really been her friend and she's opening up to me like that, not maybe because I'm the right one for her or that I deserve her but because I'm the only option. I feel like I'm taking advantage of her.
I don't know what I should do. Are my thoughts valid?