Stay cool, mate, finasteride is a good boy at thickening that kind of thinning.
Give it 1y+, use nizoral and minoxidil and you´ll be in a very good shape. I bet my right hand you will.
I don´t think your hair looks that bad wen dry, keep it same lenght as the pic and you´ll look fine. Remember you took the pics under a flash light.
By the way, my hair looks almost exactly as yours when I was 18. I wore lenght shoulder hair, and my part became wider and wider and I had to cut it. It was horrible. I had a huge bald spot in the vertex and diffuse all over. Now after treatments it is looking quite good. It took me a great deal of patience and anxiety, but it deserves the effort.