Dont give up - my daughter was the same. Every night, she would wake up crying at least 5 times and each time, we had to carry her until she fell asleep. We tried everything but nothing worked until suddenly about 6 weeks ago (when she was 20 months old), she started sleeping through the night. Since then, she has done the same except for one or two nights but only then, she woke up once or twice. We found that she does not like to have any blanket covering her so if we let her sleep without any covers, she is fine and will not wake up. Of course, we have to make sure she is not getting cold but she seems fine.
try to discuss the time schedule and see whether any problem, e.g. the time to have milk, play for how many hours? last naps taken at? to see whether any common point?