gemgirl514, life as you knew it *IS* over. But that doesn't have to be a negative thing! Having a young baby is all-consuming. The good news is that as time goes on, those all-encompassing, must-be-met-immediately needs diminish. It will take some time, but sooner than you know you will be regaining some of the "freedoms" of your past life. And in the process you will gain a lot that you never expected to. I used to go to bars or movies with friends; now I have new friends and go over to their houses so our kids can play and we can have some much-needed commiserating and adult conversation.
As time goes on and your baby does more (besides eating, peeing, and pooping), you will probably start to feel like your life is fuller, and not just that you've lost everything you were familiar with. It's kind of like moving to a new city or going off to college -- those can be really hard at first, but you often find after a little while that life is much richer than it was before. With a child, you "rediscover" things you have overlooked for so long. Christmas becomes much more fun. When a 2-year old asks why leaves fall off trees in Autumn, you stop and think and notice all the leaves around that you glossed over for so many years. Toy stores, children's books, and nursery rhymes are fun again.
There are two things I would highly recommend you doing. First, when you feel your baby is ready to be out, get out of the house EVERY day, even if it's just for a few minutes. With a new baby the preparation for getting out of the house can take longer than the duration of the trip, but it's worth it. You have to get out in the world to stop feeling cut-off and isolated. Whether it's a walk in the park, a trip to the mall, or grabbing a drink at Starbucks, it's good to reconnect with the world outside. If you take your new baby in public, I bet you will feel like a star again, because absolutely everyone will want to have a look at this tiny and wonderful creature YOU have created!
Second, seek out mom's groups with moms you feel comfortable with, and seek new friendships. You may have to try a few to find a nice fit. Try to be proactive about forging friendships. Almost EVERY first-time mom finds herself suddenly isolated and without other mom friends. So chances are, if you see someone with a young baby, she is starved for friendship and company, too!! Or if not, you can join in with her and people she already knows. Hang out in places where other moms are like parks, children's museums, etc. Online friends can be a real blessing, too, because you can read or type an email at 4 am when you are up feeding baby, whereas you sure can't call someone on the telephone at that hour!
You know, I had a sort of a mini-breakdown when my DD was 4 weeks old. For unknown reasons, I went through a spell where I felt so fed up and angry. Here was this little creature who was demanding seemingly twice what I could give. Nothing I did felt good enough. I had expected to be such a great mom, and felt like I sucked. I felt wildly hormonal and like I wasn't in control of my body or life. From what I remember, the anger only lasted for a week or two, though, so hopefully your case will be similar. My daughter started to get on a "sleep more at night, wake more in the day" schedule when she was about 8 weeks old. That made a difference because I felt like my life was (slowly) returning to a slightly more regular existence.
Last but certainly not least, it is not at all unheard of to "relactate" -- and the earlier you try, the better the odds of success. If you would like to give breastfeeding another try, do not hesitate to look for a good lactation consultant in your area. IBCLC certification is a good indication that the Lactation consultant is well-trained (hospital LC's are often not IBCLC and frankly, not all hosp. LC's are that great). You can also get support by contacting the LLL group in your area. You don't have to breastfeed to be a good mom, but if you feel cheated of the opportunity and guilty, then you can always give another try! You'll instinctively know when you have given it more than your all - and maybe you've already reached that point, in which case you can trust that you did your best and begin to move on. But if not, consider trying again. The breastfeeding hormones are pretty nice when all else is crap.
I know for a certainty that becoming a mom is harder than expected for EVERYONE. There is the old joke that if women knew how hard it would be going in, no one would procreate. But the expansive feeling of your soul growing to incorporate another being makes it worth it. And contrary to popular belief, that expansion is gradual. You don't feel the full capacity of love for your child right away like the movies show. Like any other relationship, the mother/child bond cannot be hurried and will continue to grow and grow over time.
Hang in there. You ARE doing a GREAT job!!