I've lost me

There seems to be no me left in me. Between taking care of my son and husband then our house I've lost what makes me happy. Half the time I dont know if I'm happy or sad or just going through the motions. Before I met my husband I was such a happy person. I'm not blaming him for my unhappiness but I eventually started to focus on him more than me. I was raised that's how a woman is supposed to be. But before I met him I always put myself first, I felt that if I couldn't make myself happy then how could I make someone else. So after I realized I was unhappy with myself as a person I went to the doctors and got on antidepressants and felt better for a while. When we decided to try for a child I quit taking them and when our son was born I poured all of me into him and my husband. When he was 6 months old I got back on the antidepressants to try and be happy again. That time I noticed that I wasn't quite as miserable but I still wasn't happy within myself.  I'm now off the medication again and pregnant with our second child, and I am so tired and miserable that I can barely find it in me to get ready for the day. I wish I could blame this on hormones but I think all they do is heighten my feelings. I'm not even sure it's depression anymore and I feel like maybe I rely on the medication to make me happy now. I just wish I could find that part of me I lost all those years ago. I want to be that person again, to somehow get that part of me back and use it to make my family and myself happy. As of right now I feel that I'm not the mother my son deserves or wife my husband needs, and with another baby on the way I don't know that I'll ever be that happy person my family deserves. I'm just lost.