Can I ask a question , have or will any of your mates offer for you to go to them ?
Or is it a case of they drop you like a hot $hit as soon as they had kids and stop making an effort to see you , call or text , which is all so common these days
If I was in your shoes and none of my mates offered for me to go to them I would be pretty pi$$ed , even if you decide not to go, they know you are on your own and would nice to be asked
For the future you should concentrate on getting a new circle of friends , I would join a club or team with others of similar age there will normally be a good social circle as part of it , enjoy yourself and see what happens
If you can afford it and you dont go to your mates , a few nights away abroad Amsterdam ? Prague may be just the ticket
Good luck mate