Just to throw in a bit of support, not really anything useful on the whole 3am waking thing:
Roslily, I could have written your posts when DS was tiny. As Starlight and many others will testify, I was desperate for the 'solution' to DS's various sleeping habits and problems, and found it incredibly hard to adjust to not getting any me time (despite DS being very much planned, wanted, expected and 'prepared' for)
I came at things from the other angle - I was determined to GF (with a baby that was patently not GF-able and plain old didn't need that much sleep to be perfectly happy). I perservered for months, so I admire you for recognising that what you were doing (APing) wasn't working and trying something else.
However, the big change came when I finally managed to relax when DS was about 5 months. I basically decided that
(a) I wasn't getting any me time (except the odd break when DP was there) till he was 2. I don't know why I hit on 2, but I think I decided that if all else failed we'd scrape together the money to send him to nursery a couple of days at that stage. Once I accepted that, things got a lot easier. And I actually now get plenty of me time, and have done for some time. I just accept that it sometimes comes at funny times (the odd random 2 hour nap, or a sit down at a baby-group-friend's house when he'll play happily for an hour which he won't normally, or a bath in the evening because I had a good night's sleep the night before and know I can cope that night with an hour less). A lot less than I used to have, but plenty for me to feel human.
(b) I wasn't getting a full night's sleep until DS was 2. See the reasoning above, replacing 'send to nursery' with 'controlled crying'. Again, it didn't last that long (DS started sleeping 10 hours reliably at about 10 months), but accepting it was key to relaxing about it, and knowing that I was prepared to do something drastic when the 'deadline' of 2 hit.
(c) The dream feed just didn't work. DS didn't go a minute longer than he did without it (woke at 2am with a dreamfeed, woke at 2am without it). I made myself feel better about it by offering more milk during the day, but not sure that made any difference to him. I just randomly dropped it one day and the only effect was to let me go to bed a bit earlier.
(d) I decided what I was and wasn't prepared to do. For instance, I didn't want to feed to sleep, because I wanted DS to not be reliant on me to sleep (meant a longer break for me if DP could get him to sleep!), so I just never did it. But I was happy to walk for 3 hours a day with the pram (the only way to get DS to nap for any length of time), so I did. Decide where your limits are, and stick to them. It'll save a lot of 'how do I stop BFing my 2 year old to sleep' or, 'I can't leave the house, DS will ONLY nap in his cot!' threads in the long run.
Also, at the end of the day, I just don't desperately like the newborn stage. If I could produce another one year old from under the table instead of having a newborn again, I would, happily! It was, for me, a question of simply surviving until more fun bits. And I say that as someone who loved and adored DS from the day he was born, never had any bonding issues, but just didn't 'get' the newborn thing.
Ummm.... That was a bit of a brain drain, but hope you get some reassurance from it! You're not the only person who ever felt this way by a long shot. Hope things improve soon!