At a bad place guys, pretty sure we’re tailspinning.

So we met when I was new to a city and then got engaged a year after and married 3 years after that. Been together for 5 years now. We’ve had some good times but have argued more and more. She and I are very different people but when it’s good it’s really good. Sex has pretty much ceased to exist unless one of us is drunk. I feel like she controls me and she feels like I lie to her. Just signed up for marriage counseling but I’m sure it’s too late. Her dad and sister died during our relationship so I feel real guilty like I’m not supporting her. I’ve been smoking off and on, and she found me the other day and said we should separate. We’re kind of in a limbo right now. Luckily we don’t have kids, though she wants us to have her nephew move in soon. Need help, or advice.