Getting 7 month old into deep sleep

[sleepyniki]

My 7 month old sleeps from 7.30pm until anywhere between 11pm and 2am. She'll then wake for a feed, fall asleep but wake up to feed again every 2 hours. I know she's using me as a dummy (she's exclusively breastfed) but when I've tried alternatives - dummy, water, leaving her to cry, rubbing her tummy, pick up/put down - it results in an hour and a half of screaming which I can't bear. She naps well during the day, has a good routine, falls asleep by herself at 7.30 and is in her own room (we moved her at 6 months but this had started before then).
I feel like I've tried everything and am exhausted so any suggestions are welcomed! Do I just need to be tough and persevere with the crying?

I'm afraid she sounds completely normal to me. This is more or less what all three of mine did.
There's lots of options, controlled crying, cry it out, no cry sleep solution, gentle withdrawal. I found that what worked best was passage of time. Sorry this isn't what you want to hear, but by the time they were all walking and eating (approx 14 months) things improved enormously.

Thanks Stainesmassif. It's actually a big help to know that it is normal!

After I had ds2 I decided to take the path of least resistance and do whatever made the tiredness bearable in the day. Walks outside, lots of coffee and chocolate helped.