Winter can be one of the hardest times, the lack of light and warmth (depending on where you are) can truly affect some people. I know I often tend to get the blahs or feel down more often in the thick of winter, usually January/February are the worst. Some people actually go for phototherapy when they suffer from winter depressions.

You've had a lot happen as well, but I think a big thing is you will often feel you aren't liked or accepted as long as you feel dislike or unacceptance towards yourself. I think the more you learn to accept and like yourself, the less you will feel those feelings of being alone and unliked. It has a nice beneficial side effect of making you feel more confident and confidence tends to draw people too. There is no exact way of doing this, I think everyone has different things that help them in this way. I hope you are able to find some answers but I think they will have to come from within you in order to give you a more lasting feeling of peace.