Should i throw in the towel and give up on our relationship?

Sometimes I really hate (and I know that's a strong word) my boyfriend but I also know how much I really love him. Lately, we have been having a lot of ups and downs. More downs than ups. We just can't seem to get along and I really don't understand it. I don't see where I am doing anything any different than I ever have. When I try to communicate with him he just shuts down. Things used to go so well not a arguement or crossword in the first 2 years. Every moment was great and cherished. Now I feel like I walk on eggshells and if I voice an opinion it will lead to disaster. Like tonight for example, we were talking about something and I told him that it hurt my feelings and left the room for 15 minutes came back and he hasn't spoke in 3 hours. He use to be so attentive and aware and concerned if he knew he hurt my feelings. What the heck happened. I'm just generally unhappy with him right now but I love him so much. I am still very attentive and let him know I love him even when he is a jerk. I feel like I give give give and get nothing back. That's the major issues. I just really want things to go back to the way they were. I felt like we used to be so inlove. Don't get me wrong I know he loves me and he takes care of me its just that I miss the way things were. Actions speak louder than words. Other things have come up lately too. Like I disapprove of how he is parenting his daughter. Also, after telling me that he would have another child - now he says never. Is our relationship doomed? I don't know what to do. I love him so much and I am not strong enough to leave.