So glad that you're getting better. Sounds like you're getting a good handle on things, and the more you do, the stronger you'll feel for tackling the next thing. Glad to see that your family is helping out too.
If going to the wedding is something you want to do, then by all means go. If you think that you need to heal the rift in the family, you'll just be stressed and anxious about it. Just think of it this way, we all have our lessons to be learned in life, and this is one that your son and daughter need to learn from. You'll cheat them out of an opportunity to work through their own issues if you try to control their behaviors now that they're adults. And, as my DH says (he saw this on a poster once): "Never try to teach a pig to sing. It's a waste of time and it annoys the pig." Corney I know, but it's easier to catch myself or have DH remind me that sometimes I'm just trying to "teach a pig to sing" and it's really out of my control. Maintain your relationship with both of them, and let them work out (or not) their own problems.