Baby blues or depression

I love my son very much. He's the only thing that make me happy. When I'm away from him or he's sleeping I feel like deep pain of loneliness in my gut. I can actually feel my heart straining to work. My husband isn't affectionate anymore. He's not really around even when he is. He's constantly on his phone or complaining about us and even the dogs. He's rarely even nice to me and even when I try to plan date nights he's not interested. I can't leave because I can't afford it on my own.