It is extremely tough to carry on when it feels like life just keeps dragging you back and holding you down and making you suffer. Every minute you hang on and push on through is a massive achievement, and even if it seems small, it is still progress. One step at a time.
Crying is not a sign of weakness. Most times it is so much better to just let yourself feel your emotions and let them out so then you can start trying to move forward again. Holding emotions in can really have negative effects and end up building up inside you until you feel like you're going to explode completely. So do not feel ashamed or beat yourself up for crying.
That being said, I know how terrifying it can be. I often have breakdowns and panic attacks and I know that in those moments it is incredibly difficult to see or feel anything else. It seems so much easier to just give up and admit defeat. But you are not defeated, you are still winning at life even if it doesn't seem like it! Each day you get through, you win some more at life. It is also really really scary and like you said you feel so lonely. But you definitely are not alone! Please please message if you need absolutely anything. I know I, and the others in this forum, care about your wellbeing and would really like to know how you are doing. Sending big love and hugs xxx