"Disgustingly" Skinny?

I am 5'6 and my weight tends to fluctuate quite a lot (average is 105). I am self conscious that I have hardly any boobs and no butt. I want to say that I have been skinny MY WHOLE LIFE. I remember when I was a kid everyone would make fun of how skinny I was. Back then it was due to high metabolism on top of me being a picky eater. Now, I eat a wide variety of foods and, I will admit, I have gained more weight since high school but it is hard to go up higher (I have tried through healthy, and also unhealthy, methods. Right now adding butter to everything I cook). I am very self conscious about it because I have had people tell me to my face "you are disgustingly skinny" and "do you even eat?". I am worried because I never had a boyfriend (though I was not really looking before) and that my "skinniness" will turn them away. From what I have seen my spine does not really show when I bend over and only if I stretch does my ribs slightly show. Other than my weight I am extremely healthy, I rarely get sick and have no health problems and am regular. People have told me I should exercise but I am scared people will look at me as some skinny girl who is trying to burn weight and during Uni I hardly have the time. What I am wondering if my body looks "sickly" or "unhealthy" or unattractive. I added the pictures I could find, all but one are from this summer. Haven't taken any recent ones. Thanks!

i170.photobucket.com/.../photo_zps8d0cb075.png

i170.photobucket.com/.../photo2_zps1146b02f.jpg (older one from Christmas 2013)

i170.photobucket.com/.../photo_zpsb327841a.jpg
"Disgustingly" Skinny?
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