We Use to be Happy & In Love, Now We Have a baby and.....?

In sum of the past few years, my fiance and I met. We fell head over heels for eachother. Our biggest hurdle is our ages, we are 17 years apart. Last July 2006 I got pregnant. My little boy is now 6 months old. You would think everything was just peachy, but its the sheer opposite. Ever since I was about 7 months pregnany, our level of intimacy has reduced to about one a month or less...he doesnt kiss me or show any esire to be intimate. I am trying so hard to deal, but I dont know if I can. There are many other elements as well...his two kids ages 9 and 14 who are very spoiled and his daughter is VERY bratty. I am expected to watch them every weekend while he is at work, while their mother goes away for the weekend?. We just finished taking almost a month break from eachother, but things are not that diffrent. He keeps asking if we are going to plan the wedding for this spring or summer, but I have no desire to?! I feel like I am beginning to loose intrest in him?I am so confused.HELP