LaCrousse, a lot of people share your loneliness and resulting difficulties. You've already heard my advice, but I'll elaborate with this. You have to force yourself to get out of the house every day, even now as you contemplate what interests to pursue. And if you have to drive somewhere to do it, or stop by somewhere after work, then so be it.
Whether it's the grocery store, a walk in a park, gym, library, coffee shop, or restaurant diner where a waitress serves you. Even these simple activities allow you to have some daily social interaction beyond work. They will give you little "fixes" of desparately needed attention while you seek something more substantive through clubs, organizations, or church.
The thing is, when you go out, you need to make a commitment to yourself each time to be assertive. This starts by looking at people and seeing if they return eye contact. If time permits (an elevator or line being perfect), you need to be the one to grasp the opportunity. It's easy once you consider that if someone looks back at you, that's your cue that it's safe to smile and say hi, how you doin' today? In most cases, that'll only yield 2 seconds of reward. But even that's worthwhile, because you not only gave yourself a social interaction fix, you made someone else feel important and good for a moment too. In some cases though, I find such contacts with strangers will say more, allowing opportunity for a small chat. And if I build a routine of visiting places repeatedly (like a gym bar, or restaurant), any previous contacts made almost always yield more time and conversation with each reconnect. Point is, you have to get out - to anywhere - and initiate contact frequently. The many daily fixes of social interaction won't immediately solve your loneliness, but they will help you enjoy each day more and cope with the loneliness better. And, eventually, a casual contact can become a friend. Let me elaborate on my own situation.
I retired 4 years ago and am homeless, travelling the world full time. I have many friends all over the world, but none in my daily life. I get tired of going out and love just staying at home and doing my internet projects and watching a movie. But, I recognize my own loneliness, so I force myself to go out for a walk twice a day where people are about. I always initiate contact with every opportunity - to get my own needed fix and to intentionally show Christian kindness and love to others. In the evenings, I'll often hit a restaurant/bar environment where some other singles sit around looking bored or unsociable. It's always me who breaks the ice, and I see and meet all kinds of people that I don't particularly want to be friends with. Still, I get a lot of evening long conversations, make contacts that I see again, and aquire a few that have turned into part time international friends that I reconnect with every year or two. Getting out and initiating contact is key. I like walking down a street in any small town in the world, seeing someone I recognize from a prior greeting, and stopping to shake their hand and say hi. Just a few minutes of such social interaction makes each day worthwhile. It takes initiative though; an investment of time and effort.
So, while you're fretting over the big picture and potential solutions, I'd suggest you take the small steps each day right now.