If you want to gain weight, you need to restore your gut flora asap. Otherwise it's gonna be a never-ending problem. Low-carb is not the way to go, because it dramatically reduces gut flora, unless you load yourself with prebiotics.
Now, I've had some results at first with a very low-carb diet and antifungals in terms of reducing candida symptoms, but whenever you reintroduce carbs you're gonna have troubles, because there is lack of good bacteria and the candida can proliferate once again. Remember that most antifungals are also antibacterial.
Instead, I recommend you forget taking antifungals and go for things that fight effectively candida without harming friendly flora. Saccharomyces Boulardii and homemade kefir are some of those. Also, even if candida might be able to feed somehow on it, eat big amounts of jerusalem artichokes for the inulin content. It is the best known source of food for friendly bacteria, and in the end you're gonna win the battle if the good ones take over.
Also, keep in mind that overloading yourself on fats and animal proteins is gonna hinder the progress, because candida feeds on sugars yes, but loves also compromised digestive systems, that too much fat and protein can aggravate.