what is the best way of dealing with them so they do not die on me...!?
if you look around the house plant forum, there are a few serious gardenia cultivators who should help-
in fact, if you search for 'gardenia care' in the search box, you should pull up a FAQ for them.
I don't do plants that need babysitting. no gardenias, no fuschias...and now, no cranky mildewy old roses, either.
Yes, try the House Plant Forum. This is a tough plant to keep happy in the typical home. You used plural when mentioning your gardenia. More than one?????
Also, mandatory reading for this topic is:
You'll find you have lots of company.
Here is a link that might be useful: Suicidal Gardenia