I also can relate to that hole on my soul. No matter how blessed I am, or how well things are going in my life, there always seems to be “something” missing. My soul yearns for “more”. I beat myself up at times for feeling this way. I know I should be grateful for all the blessings I do have. That loneliness, and feelings of sadness can creep up on you when you least expect it.
For me the answer is meditation, and trying to connect with that loving power that I know has my back. If I am to find peace, I need to trust in this power. I don’t want to get too “woo-woo”, but the bottom line is I need to fill up this yearning hole in my sole with some more spirituality rather than people places or things. I’ve done the latter way too much in my past, and I know a new car, a new relationship, a vacation etc are not the answer. Hope you can look inward and feel good about yourself, good about where you are, and confident that your higher power has got you 
