I had an affair and now i want my time with my child at my home. But the mother of the child doesn't want my child by my wife.

Generally a parent gets to decide who their children are around during his or her parenting time.

It means an order was issued because one side was ruled to get notice and didn't respond.

How often is acceptable to contact the GAL? Did I overdo it?

It doesn't sound like you've crossed a line regarding the GAL. However, the easiest way to tell is to simply ask regarding what the GAL's...

What should I do?

I agree with Counsel. This is indeed a criminal act.

Do I have to pay arrears for 2 kids that I now have full, sole, physical custody of?

I suggest motioning the Court for a modification of parenting time and child support.

Can I marry someone who lives in a different state?

Yes you can marry someone from a different state.

You can contact Court administration or if necessary review the court records to see if the order expired or was dismissed.

Am I legally obligated to give in-laws visitation?

No you are not obligated to give visitation. They may, however, be entitled to pursue an action for visitation.

Can my husband kick me and my kids out? He is threatening divorce and kicking me out on the streets?

No your husband cannot legally kick you out of the marital home without a court order.

How can I divorce my wife after being unfaithful multiple times throughout the years without giving everything I earned to her?

You can start a divorce with your wife. Things like spousal maintenance will be arguable issues based on your and your wife's situations.