I have been with him 8 years and we have a son this is not the first time he has done it I want to know if this is a sign of cheating
I don't feel he is cheating but I don't understand why every weekend he takes off he doesn't stay overnight all the time he says he is at a friends drinking but he doesn't value says he stays the night because he is to drunk to drive which I understand but he should call me and let me know. Or ask me to go get him he just has changed a lot me and him use to be so close. He has a I don't care attitude about anything and he use to be so close to our son but it's not the same he does love to drink.
It may not be cheating, but it isn't anything good. Just the fact that he's keeping secrets from you is a bad, bad sign.
You need to start having some REAL, HONEST conversations with him. Even if you're going to be mad or hurt, you need to ask him to tell you the truth, and do NOT get upset with him. People sometimes act out like this when something ELSE in their life is going wrong, and he may be embarassed or ashamed to tell you about it. Maybe he needs help. He could have a drinking/drug/gambling problem, or owe someone money, or some other thing that he's dealing with that he needs some help with.
But don't put this off: you need to deal wiht this ASAP, in a non-judgemental way, and fix this relationship, or it's going to be over before too long.
My mate comes and stays at my place quite often, and I sometimes ask him if he lets his girlfriend know where he is. He usually shrugs it off as unimportant, but I've talked to her myself and assured her that he's not up to dodgy business.
Having said that, if concerned you should ask. Guys don't always offer information, but unless they do want to hide it, they aren't going to be fussed about telling you.
He doesn't exactly have to be cheating, but he could be out having a good time with his friends having a Bro's Night. No matter what he's doing he shouldn't be staying out all night without a proper reason ... I'd be concerned. And I'd ask him about it...