it's not even a 'wedding invite' it's reception only!
go on your own you big wuss, and give thanks to GOD that your DP gives enough of a shit about his children to want to go!
this is not just a kickabout in the park, or even a school game, this is League Football, this lad must be really good, so has a chance of making something out of it.
an evening invite means that only, go on your own, you don't have to stay for long, who knows, you might even enjoy yourself.
never ceases to amuse me at grown women not being able to attend things without their OH, you don't melt you know, people don't point and laugh if you go alone.
what on earth did these women do about going out before they were joined at the hip with a bloke?
EVERYONE at the wedding would understand about why your DP isn't there, and they'd admire him for it. they'd admire you too for being so 'sorted' about it.
you've got the outfit/shoes etc, so GO! is there a chance your DP could pick you up? so he could put his head round the door and wish the couple well when he comes back after the football?