Lonely and bored of life

Im 21 and I've been diagnosed with depression and anxiety officially 2 years ago, although i felt like that since early highschool. To me life makes no sense and nothing gives me pleasure anymore... I've only had 4 friends and i i feel like I've been sucking the life out of them wit my negativity but i dont know how to act anymore and I'm extremely scared that those 4 will leave me like everyone I've ever known...