Is depression linked to anxiety in any way?

Yes. They are two sides of the same coin. Depression is worry about the past and anxiety is worry about the future/present.

Yes. For me, any kind of boost in anxiety feeds my social anxiety. I don't get out, and that feeds my depression.

It can be linked to anxiety. Having anxiety can make you depressed by what you are having to go through. You might feel that people are judging you for the way you are feeling and that can make us depressed, so they could be linked.

Yes, there is a correlation between these two. People who are feeling depressed have a higher risk to also suffer from anxiety and vice versa. For example not leaving the apartment continually could lead to feeling anxious about getting up at all, not knowing what has changed (maybe at school, university, work) and therefore being too frightened to try. Same with the other way around, if maybe you are suffering from social anxiety and you don't dare to talk to others or even strangers, it might leave you feeling depressed for being lonely... That sounds much worse than it actually should, so let's just leave it with: Yes, there's a correlation between depression and anxiety :)

I personally think that you don't have to have depression to have anxiety and vice versa, however, I do think that they could be linked as to be constantly sad and have low self esteem would bring on anxieties and that anxiety can bring on feelings of depression.

Yes, those two very often go hand in hand, and sometimes anxiety can be an introduction to depression

It certainly can be. You can be depressed because you're sick of being so anxious and the stress is making you feel exhausted. You can be anxious because you worry you'll never stop being depressed, or because your depression keeps you from getting necessary things done and gives you more reasons to be anxious. I've definitely experienced all of these things.

Yes, I think that depression is linked to anxiety, because people thoughts about the future are normally based on past experiences and usually depression is based on that past experiences and when a person suffers from anxiety, may remember the negative experiences instead of the positive experiences and it increases the levels of anxiety and may increase the depressive thoughts.

I'm pretty sure that anxiety causes depression most of the times. When you feel like you can't go outside and enjoy others company or going places, I don't know, you begin to feel sad. There are times when people get paranoid because of anxiety, startind to believe that peiople avoid them, and that's a bigger issue that "helps" with depression.

Absolutely. Anxiety can be very stressful and make you feel very down and confused. This can definitely cause the sufferer to experience depression in some way.