Another solo walker here, like many others here, I'm not anti-social or anything, nor am I lonely or a loner, and I'm not against walking with others. I will strike up random conversation with people I pass, and can sometimes be a bit of a natter box, so I apologise now for your sanity, if we bump in to each other, ha ha!
I find I'm a solo walker by circumstance rather than choice, none of my mates go hiking or camping, plus a majority of my mates are spread all over the UK, so getting together is a bit awkward.
Plus I’m a shift worker so I work most weekends and bank holidays. This brings the advantage of missing the crowds on popular walks. Walking alone is not ideal, but I have found a sense of freedom of being solo. I have become use to it and quite enjoy it. I can go where and when, and take breaks when I want, at whatever pace I want.