Life just seems incredibly lonely without someone to love. Someone to share your day with. Share your thoughts and fears.
First, learn to love yourself. Second, you will have relationships in your life again. What did I learn in not being in a romantic relationship for so many years? That there are relationships that aren't romantic where you can share yourself with others. Cultivate friendships.
You are 40. Once you do your work, some friends will come along, and one day, another romantic relationship. Your life isn't over. You'll miss that partner for a while, but its not the end all be all of life.
