Count, my first DD was just as you describe - my whole life revolved around getting her to sleep, to make sure she wasn't completely overtired. DS is the same. I just breed em that way - and reflux doesn't help things.
When DD got to about 6 or 7 months, there came a day when I just could not bear another 24 hours of the same. I'd truly had enough. I put her in her cot and stayed with her, with a hand on her tummy, until she went to sleep. SHe was livid, really screamed, and it took a looong time (e.g., 2 hours plus). I also think in fact my presence just made her crosser, but it made me feel better about not leaving her alonen. The next time I put her down, it didn't take as long. The next, shorter still. By the fourth time she went down and put herself to sleep, which was a massive improvement and I felt utterly liberated that breastfeeding was not the only way she could fall asleep. This is the method that Elizabeth Pantley recommends as a 'last resort' strategy if you have tried no-cry, it hasn't worked, and/ or you are at complete breaking point and getting to the point of resentment. But it may not be for you, which is totally fair enough.
Now, my DD was definitely a child who was a 'tension increaser'- e.g., got more worked up by crying so I dind't think that kind of method would work. But it did. I won't say we didn't have any problems after that but it really did mark a major turning point for us. By 9 months she was generally taking fewer, longer naps, and wakening in the night only when she was hungry (she really was - big lass, no interest in solids).
Now, my DS is another matter. He is 18 weeks and terrible day/ evening sleeper. I have said to myself that I am going to do the same with him as I did with his sister if he is still appaling when he reaches 6-7 months or so.