Another Lonely College Freshman With No Direction In Life

hello everybody. i have had times of sadness before (never medically diagnosed as depression) over my life, or what i thought to be, but things are different now. i
have this to be thankful for - i'm making excellent grades, which is surprising because my A.D.D. (diagnosed) has pulled them down most of my life. i tried to think of something else, besides my family, but i honestly cannot thing of anything.
three different things have caused this depression

1. loss of creativity and focus. i am an artist, or was, i guess. i have never felt so dry in this way before. every time i start a new piece, i lose inspiration or direction and get bored with it. the idea of even doing art drains me and seems pointless. i haven't done anything in four months.

also, i once considered myself a reader and writer - neither interest me. for the first time in my life i haven't been able to finish a book or write anything that satisfies me.
i used to run seven miles a day, now i do not run at all.

i feel like everything i do is pointless and crappy.

2. i'm lonely. i had a group of what i thought to be close friends in high school, now they are spread across the country. we used to stay in touch, but they've (understandably) drifted away now and we rarely even talk. i go to a community college. my parents drive me everywhere because i cannot afford a car and just have my permit.
i am pretty sure i am a friendly and attractive person, and i get along with people fine, but i never connect with anyone. plus, most people are about twice my age because of where i go to school (i'm eighteen, most are at least 25). even if i was invited to go anywhere or whatever, i wouldn't because i am embarrassed that i cannot drive. i spend most days alone in my room or cleaning the house.

3. i am afraid for the future. i used to think i wanted to be an writer or an artist, or maybe even take a biochemistry major. i have reoccuring fears that if i do not choose something soon, i will never get out of my parent's house no matter how good my grades are.

i also have somewhat dramatic fears about the environment. i do not want to have children because i think this planet is slowly falling apart. i am not talking apocalyptic stuff necessarily, but i feel that in ten years life here will be unbearable for me. i cried today because i have (irrational? i don't know) fears of no more sun or clean air.

this subject alone makes me have suicidal thoughts.

also, everything around me (mostly family-related) saddens me. for instance, my mom is a chain smoker and is generally unhealthy. i always hear her breathing in the other room, she sounds like she is suffocating.

feeling this way is fairly new to me. it actually makes me feel guilty, because i know how lucky i am. on the outside, i seem healthy and peppy and adjusted. my mind, however, constantly is telling me that everything is pointless and anything good about life is over...
actually, i don't even know what the point of this is. i guess i've been keeping this all inside and needed to put it all somewhere where someone could read it... thanks.