Why do people always think Im staring?

I'm not staring at other ppl, but for some reason they always think I am. I am a 37 y/o female and this has been happening to me since I'm 15 and am tired of it. for example, I was out of town over the weekend, and was exploring this small touristy town I'd never been to. There were these two women walking by, one maybe the mother or aunt both very attractive and well dressed, and i had to walk between them bc they didn't create space for anyone as they walked side by side. I heard the young girl about 15 or so say "everyone is staring at me" and the mom or whatever she was say 'yeah they are". i was not even staring! I was a tourist looking at the stores and they just happened to be in my line of vision. Then last night I went to the grocery store and this big overweight woman walking w her children walked by me. i moved my cart for them, and was literally looking at the salads not at them. and she said "don't be staring at me" to herself. 

I have large bright blue eyes . that ppl often comment upon. could this be why? but what am I supposed to do??