We rarely had a good night sleep my son's first 18 months - but otherwise what you are saying sounds somewhat familiar. My pediatrician told us at 8 months the baby should be able to sleep without night feedings (at least 8 hours). Starting around that time we were able to wean the night feedings, but then something would happen and I would feed him (like ill, or teething, or desperate for sleep when he did wake up). Then he would expect one feeding every night, then a few days later he would always wake up twice a night, then a few days after that he'd wake up three times each night. Each time this trend got started we had to get tough and do Cry it Out, and since I was the primary nurser - I did have my husband be the one to check on/soothe him (which I know is not a luxury you have).
Since you are single, thus the primary bottle provider, this is going to be harder for you. Ideas to try -
Cry it out, but check on him, pat his back, give a reasuring 'shhh" every several minutes so he knows he isn't abandoned (although you might just have to let him cry at his age, my own son did worse if we came back in at that age). It sounds like this is working for you - waking only twice versus 3-5 times. If he does have a "serious crying bout" go in to him, but don't pick him up from the crib and don't give him a bottle of formula. Just stay with him and sooth him. If you can stick to it for a week, it will probably get better, or even be a non-issue by then (if it doesn't get better in a week then you need to reevaluate and do something different)
Bottle of water - we provided our son with a sippy cup of water and that seemed to help. He could find it at night on his own - he still has it at 2.5 yrs old.
Stop indulging his night feedings - who wouldn't wake up for a good thing if they can get it. I know this is hard though, that is part of why I had to wean my son from night feedings at least 3 times. What helped me sometimes was reminding myself that even though it is harder to be up with him right now and soothing him without food, in the long run it will be easier because he will start sleeping through the night sooner. Other times I was too tired to care and gave in, and I know it prolonged the issue. Hopefully you'll be able to hang tight better than I did.
Sorry, I can't think of anything else. We struggled until my baby was about 18 months to get him to sleep through the night consistently - but a year later I am just forgetting all that it took. I guess that can be read as good news - you will get through this and then it will be a thing of the past.
I hope this made some sense, I think I rambled a bit. Good luck, know that you are not the only one, and that it will get better.
State Certified Early Childhood Special Education Teacher
New Mom as of March 2009!