when did you have the ablations? I agree with the previous poster that if you had them long ago it isn't likely the problem though people who are young can see their hearts repair themselves. It is also possible you have another type of svt that went undetected until now. It isn't unheard of so as the previous poster suggested find a good EP and get a monitor to catch the issue so you know what is going on. Take care and keep us posted on how you are doing.
If the it has been a while (months or years) since your last WPW ablation, then your doctor's guess of heart getting damaged via ablation is probably not correct. You need to have an EP that is good at ablations look at your holter and past procedures. The fact that you had 2 ablations and didn't have the WPW successfully cured is a warning not to use the same center again. There are pretty good choices in your area starting with UCLA.