Hi Sleepy....
Can I just say that I totally, *totally* can relate. I remember very well those feelings of being lost, wondering if anything I thought was true about myself was still actually true. Moving to a new country will certainly bring those feelings out in a person.
One of the biggest mistakes people make when they move here from the US is to assume that it'll take as much as a few months to settle in. Actually, the truth is, it generally takes more like a few years. I've been here nearly two years now and I can honestly say that it wasn't until the last few months that I have finally started feeling 'adjusted'.....mind, I still get homesick, still miss the US, and all of that, but I am feeling better.
Like you, I'm from the countryside and moving to London has been a serious adjustment. But I think moving to any major city would have been hard....the fact that I had to give up everything that defined me and that I loved sure didn't make it any easier.
I can totally relate to your dog story by the way. I had to leave my baby behind to, and unfortunately she's since passed away...talk about guilt!
Anyway, what helped me is making friends, finding hobbies....all those things I'm sure you already know about. If all else fails, there's lots of us in and around London that would be happy to meet for a cup of joe or something to cheer you up....or at least let you know you aren't alone.
Just holler! We're here for ya!