You can believe in the part of yourself that wants that belief, and you can believe there is good n the world and that you can help there be more good in the world. That is your best self and you don't need to discard it because you learned ttatt. You just have to find a different way to express it. It's not a one size fits all kind of thing, but a journey that we each must go on. First you need to figure out yourself, what makes you tick, what is your passion? The Watchtower had us so stuck in a mold you may not even know what that is. Meditation and journaling may be helpful here.
As an example, you may find you miss the religion, that the idea of helping others in a spiritual way is still appealing to you. You could visit a few churches and see if any resonate with you. If you find one, you can think about getting involved. If you are turned off by the idea of a church, there are ways to help others in a spiritual way. You do not necessarily have to believe in God to do this. No matter how old you are or what limitations you have, you can still believe in something and still express that in your life.
What you end up doing may have nothing to do with religion, but if is your passion, it is what is right for you. It's a journey, not a final destination kind of thing. As long as what you are doing what is in your soul, you are on the right track, no matter how odd it may seem to someone else. Maybe you are an artist deep down, maybe that is the gift you need to bring to the world. If that is the case, then that is what you need to do, and you will know when you have found it.
For myself, I realized that I was very drawn to nature as a child and I also enjoyed arts and crafts. As an adult, I developed an interest in dried flowers, that interest led to a love of gardening and also antiques. At first I didn't accept that this was what I should be doing, it seemed so trivial. At the time I had a good career, so my other interests didn't seem important enough. But no matter what else I tried, I kept coming back to it and now I love what I do and I do it full time. I am fulfilled in a way that I didn't seem possible when I was sitting in a cubicle writing code. People tell me all the time that they are inspired by the things I make, and that feels really good.
I hope you too can find something to believe in