I feel like I am unlovable

I've been looking for a relationship for 8 years now. In those years, only 2 have ever been genuinely kind to me. 

The girl I've been writing about is still here. We're close friends, she came over that Saturday to spend 7 and a half hours with me. She said that I'm the nicest guy she's ever met, and said that I was 'so sweet'. I've never heard this from anyone- nor been treated the way she does. 

I just feel like I am unlovable. I've been trying so hard, but it never works out. Not even with this girl, who currently appears to not be ready for a relationship at all. I just don't know what to do, or where to look. 

I'm just a hypersensitive autistic person who more than anything is afraid of being alone. 

It is not 'physical love' I want, not even kissing. I just want a companion who would simply be there for me when it matters. I always just wanted this.