how good a job are you doing understanding your family’s needs? if they need the example and witness of a good Christian, then give it by your words and actions, primarily toward them. Rush cheerfully to obey your parents in all things that are not sinful. Do your duties promptly and cheerfully without grumbling, and be kind, always kind, to your siblings. Look for ways to do more for them especially for your parents, and to spare them more work.
above all do not use your private devotions as an excuse to get out of obeying them and doing your duties. arrange your prayer schedule around your parents needs not yours. If you can get to Mass and confession do so (by walking or bicycle of necessary). ask yourself, if I wanted to get to the mall or rock concert and my parents couldn’t drive me would I find a way to get there? If you absolutely cannot get to church, there is no obligation.
Your parents will be much more convinced of your conversion and understand your need for the sacraments by your example in living your life–your charity, kindness, meekness, obedience, cheerfulness, courage and so forth–than by whining about your needs.
if your greatgrandmother really needs you and you could be a help and protection for her, that may be a great solution
saying the chaplet at precisely 3pm is a suggestion, not a law, it is always 3 pm someplace in the world, for instance on EWTN it comes on here at 2 because we are Central time. Unite your prayers with those praying at 3pm someplace in the world. also going to the adoration chapel is a wonderful practice, but not required, so you go when you can. Your parents are not likely to be impressed with your faith if it makes you constantly challenge them and put them down.