Okay, bub, not a sob story at all. Very common.

ealised that I don't actually have a good group of friends, at all.

Very common at your age, no matter your social status before. Once people start families, friendships often take a back seat in Ireland.

It's such a strange feeling of loneliness and I wouldn't wish it on anyone.

Not usual at all. In some ways, an inevitable function of our society. The answer is shared interests. Find a group/club/org that you can join to kindle friendships.

Do I take a chance and move in with random strangers?

Yes, do it.

How can I move on and be happy?

Find organisations that have a goal you believe in and join them. In my (very personal - YMMV) experience, happiness follows purpose

And before someone says it, I'm grand like, I am OKish.

Look it, you're probably not okay, and that's okay.

In my experience, most people have an idea of what would make them happy. What is it for you?

Is it working with people? Is it operating in a team? Is it working with machines, or organising people, or solving abstract problems? What's your dream job?