I feel like isolating myself, but deep inside I am very lonely. What do I do?

You may consider finding and exploring what makes you feel lonely. You can find people you can connect with or find hobbies. If there is something in your way of doing so push yourself to do it anyways or work towards it. It is not always easy finding people you can connect with and it can take time. Be patient with yourself and understand you are not alone. Try joining a club you might be interested in or find volunteer options around you to get yourself out there. Or start by going out in nature, observing life that is not human. Appreciate all the other things on earth that make us a whole. All of these things helped me and I hope they will help you too!