Kept in the dark by parents

 Before reading this you need to understand i am not told much about my moms situiation. My parents like to sugarcoat things and not quite tell me the whole story. 

My mom was diagnosed in 2010 with stage 4 breast cancer. She was dubed terminal and was given a year. Thankfully she is still hanging in there. Her "main" tumor is in her chest wall on the right so they are un able to reach it. She has had radiation twice and is on her 4th chemo treatment. She has only been to 3 doctors. She doesnt want to expand and get more opinions. Her doctors current game plan is to keep her on chemo until further notice. 

There have been some complications on the way. She currently is recovering from Jaundice, from what i am told it was a swollen lymphnode that was causing a blockage in her liver. She hasnt been on chemo in over a month. From what i understand she has many tumors in her chest that are blocking her fluid flow in her body. As a result she swells really bad. When she stays current with her chemo the swelling reduces a bit or slows down. Also, i was told her cancer has "mutated" into triple negative. Dispite all the radiation, surgiers, and chemo her cancer has only gotten worse. So, as of right now because of her not getting chemo for over a month she is swollen and exhausted. Today she had to be put on disability at her work untill June 29th.

I am a full time college student. My college is 3 hours away from home, i have been enrolled since 2010 and i am an only child. I just found out today that my mom was in the hospital for 11 days. I call my mom daily and my dad, they never once told me she was in the hospital. I asked what they were doing, and how was moms jaundice. "Oh just sitting in the living room, moms on antibitoics and the jaundice has cleared up!" Im beside myself. They had no intentions of ever telling me, i caught my mom in a lie and she ended up telling me. Their reason being they didnt want me to worry because of finals next week and national sports competition the week after. 

How can i convince them that its ok for them to tell me the truth? In my family everyone hides everything from everyone. My dad never told my mom the doctors gave her a time limit in 2010. My mom never tells my dad how she actually feels or what the doctors actually said. My dad didnt know my doctor told her to go on disability 2 months ago untill this week. Im at a loss here, i want us all to be honest with eachother. I dont know what to believe anymore. How can i atleast convince them to be honest with me? I have a right to know, hell i have a right to worry!