I had the same problem with social media and guess what I did? A while ago I deleted my Facebook etc... accounts . Since then I have been trying to live more in the real present, as opposed to the one projected onto the social media, and connect with people face to face even if they are strangers and the interactions are brief. Even just smiling at people while walking on a street can make a difference, something that I find very hard to do so I have to push myself to do it most of the time.

If it's too hard for you to quit the social media altogether, perhaps you may consider to reduce the amount of time that you spend looking at them and try to do things that you like to do outdoors, or volunteer for a charity that is meaningful to you. Some people find some relief from loneliness by going to churches. I have just joined a Buddhist Zen center because I am interested in meditation.