First of all, remember that rough patches are common with anyone, whether they are a homeschooler, public or private schooler. There are some days that are just hard. It might be tempting to give in when both of you are having your patience tested.
If you are a Christian, the first thing you should do is pray about the issue- separately and together.
At the same time, try to find out what it is that your child is struggling with and see if you can come up with a solution for it. If your child wants to go back to "regular" school because they are struggling with the curriculum, then maybe a change would be a better choice. I recommend trying to find a solution to their issues before making the leap back into "regular" school.
One of the greatest lessons we can teach our kids is that when things get hard, we don't give up. We pick ourselves up and work through it. These little struggles in life help us all to be prepared later on in life when the really tough problems crop up.
If you and your child and all else who are involved finally decide s/he really NEEDS to return to traditional school, then I wouldn't worry too much. Integrating back into a classroom situation is not difficult. Your school should be able to help you make the transition.