Lately it's been harder to get out of my depression and there's a sense of dread that constantly follows me around. I'm not willing to open up to anyone because it's always been nothing but pain in the end. The older I get, the colder I become and I'd like to know how I can start feeling happier. What are some things you'd suggest?

Find passions, hobbies, learn more about the world and discover your place in it, start with happiness in yourself. When you do, others begin to notice that in you and want to be around you, and the more you find people who you can share your passions with and establish those relationships.
An old monk came up with a self-worth metaphor:
"I want happiness"
Take away the "I" for that is self-serving.
"want happiness"
Take away the "want" for that is desire.
"Happiness"
And all you're left with is happiness.

That sounds so nice when you put it that way but I'm so scared to keep going. I do have things that I enjoy, definitely. But what do I do when those things are constantly bombarded by anxiety. Thank you for responding, really!

I guess find an outlet like a dairy, music, exercise or anything that will distract you from your thoughts at that moment thats my best answer sorry if I doesn't help 😶

i've definitely gone through the same phase, and some part of me is still going through what you are going through. But I've changed. I've matured. I've become different. and I've started to love myself. Look into the mirror, and say every day, "You look great!" or "Let's rock it today!" Keep your head up high. You won't understand right away, so fake it till you make it—fake the confidence and independence anyways. And then will come a time when you do understand—when you realize that the people around you are not worthy of exhausting yourself by feeling dread. That the loneliness you feel shouldn't be felt because the people who are making you feel isolated are trash anyways. Then you'll stop caring about the judgement, and you'll start being yourself. Then you'll start loving yourself and become confident and people will notice this change and you'll have new friends who actually will care about you and love you for who you are.
Change comes slowly. But change will come. Be strong.
You can do this, because I did it.
And I survived.