@red
Wise words from red here lady "But if you wanna get remarried,then it may be better for him to stay with his father as this might be a consideration for future grooms."
Further to what I've told..
When there is absolutely no regard whatsoever to the basic relation as husband and wife, one should not think much to part with the kid. Though painful, has its own advantages as "red" has put.
Trying to have the kid with you via filing a custody case is all ok.
But there are some things which you both will have to consider.
1. The kid is already 5+ years, is able to understand many things of what is happeing around him. Mainly the friction between the parents.
2. You will have a tough time convincing the kid as to what happened between you both that you wished to part ways, [remember, it is not just for you, its for him too].
3. Eventually, the child will stop trusting either the woman, or the father and will develop a sense of unconcious hidden anger toward them.
4. If either of you may have to lie about what actuall happened etc to the kid, once the kid is mature enough and comes to know about the lie, he was told about the other parent etc, the child will stop trusting you.
5. If you keep hiding things and not lie, the kid will grow up to be a confused one.
6. If you tell in detail as to what happened between the two of you and that you parted ways, the child will grow up to be not believing in marriage.
Eitherways you both have succeded in destroying a kids life. Congratulations on that to both of your ego's.