I have been alone many times, but not lonely.
Become a friend to yourself, then you will not need someone else to validate your existence.
Don't get me wrong. It's good to have friends, but it is also good to learn how to be alone. You can learn a lot from solitude. In solitude, there are no distractions. Thus, your focus becomes laser sharp.
Start with hitting the gym bro. Like seriously, go there 6 times a week.