Please help me. A anti-anxiety tablet.

I'm a 20 years old girl...and i have become very much pessimistic and depressed in my life... I use to take stress and tension about everything in my life specially about my health because after my friend's and two close relative's death I'm very much afraid of death...right now I'm suffering from gastritis...a nauseatic feeling always...but my appetite is normal...there is only an irritation in my stomach no vomiting no abdominal pain nothing...my appetite is also normal. Doctor's have asked me to take less stress...due to anxiety my health is deteriorating...doctors have given me tryptomer 10 mg tablets which is a anti-anxiety tablet. I'm also not able to sleep properly at night... I use to wake up frequently at night. Due to taking too much anxiety I'm suffering from IBS. I really want to live my life happily...i want to be optimistic...it feels like I'm dying everyday... Please help me out please. I need your suggestion badly...i want to be happy in my life...