Don't force it
I haven't read all the replies so this may be redundant.
If you have candida that means you have probably got leaky gut or other digestive problems. You need to lay off the milk kefir for a while; try kefiring other liquids that you know you can tolerate.
Gelatin in the form of bone broths can help the digestive system to heal. Avoid commercial gelatin as it contains MSG.
Food combining is very helpful for those with weak digestion. Don't eat starches and proteins together.
Lots of probiotics and cultured veggies.
I have heard good things about candida and kombucha, but you will want to make sure the
Sugar is all consumed before you drink it. If you brew your own you can use pH strips to test acidity. Unflavored commercial varieties contain practically no sugar, as well as yeasts that COMPETE with candida.
Listen to your body as it heals. Just because something is good for someone else doesn't mean it is good for you.
If you have a systemic candida infection remember that you may have recurring symptoms throughout your life if you stray from your diet for very long. These buggers tend to bury themselves deep in our organs when we disrupt them and are very hard to get rid of. They coat the heart and organs which I'm sure you already know.
As you get stronger try reintroducing the kefir gradually. I would say several months at least off dairy.
Good luck and keep us posted!