In the Wikipedia article about the Breton delicacy Kouign-amann, there is the following statement:     The Welsh equivalent is the etymologically identical cacan menyn, literally 'cake (of) butter'.   It isn't clear from the article whether there actually is an equivalent Welsh recipe, or if the text is pointing out a similarity between the Welsh and Breton languages.  Is there a Welsh recipe called cacan menyn? 
Glacé, or candied fruit, is basically fruit preserved with sugar.  So, yes, it can be very sweet.  Even for sugar lovers, it is hard to eat much.  I would suggest using it in cake or cookies.  Italians have a tradition of such cakes and cookies that call for the addition of chopped candied fruit.  I am sure other cultures do as well. I would suggest using them as an ingredient, rather than attempting to somehow remove or reduce the sugar content.  