ok, of all those things that you have mentioned, the only one you should be worrying about is about being poor. Having said that, you don't have to leave tomorrow, but you can start to prepare your exit little by little, by getting a job or a better one, start saving, start reducing your expenses while you are there to get used to living with less, and leave when you are ready.
It may be that you leave within a few months time, or in years but as long as you have that goal and work towards it, you will eventually be fine.
IME, being a lone parent has not been easy, but I have been very happy, DS and I are much closer than we were, we simply spend more time together and I have more time for him than when I was acting as a logistics manager for my ex, and lonely is the last thing that we have been, since the ex left, the house is full of friends, we are often out and about, and my friendships have become stronger.
I have worked hard to get the life we have, we are not rich, but that is no longer important, we don't need as many things as we did in the past. We have learned that a spontaneous picnic in the park with friends is equally or more enjoyable than sitting still in pizza express. We travel a lot, albeit not abroad. I work long hours, but that keeps me sane. so in general, we are very content with our life, it is a sharp contrast from the times when I was living one day at a time.