Relationships do require energy to maintain. So, it can be a hassle if you don't want to spend energy on them. And it's okay not wanting to invest in them.

There is no such thing as enjoying being single too much. No amount of enjoying being single is ever too much. Enjoy it to your heart's content.

Well, no point in worrying about dying alone, we all die alone inevitably. Even with people on our deathbed, we die alone.