I hope you were able to enjoy your getaway some. It was good that you took some time for you and your daughter. I imagine that she appreciated the time with just you and her.
Feeling lonely is not usually about being alone. You can be in a crowd of people and still feel alone. Feeling lonely is about the perception of being alone. You feel isolated from others and feel unwanted and down about yourself.
Loneliness can be caused by a poor self esteem. You mentioned feeling very bad about yourself. That may be where your loneliness is coming from. When you feel so bad about yourself, you compare yourself to others, feel worse than them and different than they are. It isolates you and keeps you from connecting with others.
You can address the loneliness by also addressing the self esteem. Doing things that help you to feel better like volunteering (which helps the loneliness by allowing you to connect with others less fortunate than you and increases your self esteem), learn more about why you feel lonely and what keeps you from connecting with others, and focusing on the good in your life can all help. Use some of the tips we talked about from increasing your motivation to get yourself started.
This feels like an uphill battle, I know. But as I mentioned, try to take it slow. Just do some things today. Don't look at the whole picture. Otherwise, it's too easy to feel overwhelmed. One day, one hour at a time. And don't be too hard on yourself. You deserve better.