Just gonna chime in again to respond to some more specific things in your post, since it occurs to me that without addressing them or without being given more help interpreting the realisation that struggle is, indeed, inherent in life, you might come away from this with an unnecessarily pessimistic outlook... also this is just a topic that interests me philosophically.
I've been thinking about this. Is it possible for someone to rarely experience emotional distress, anxiety, sadness etc...in their life and have pleasurable moments, at worst boring ones?
It's possible yes, but typically not without struggle, and a good degree of luck. Also, suffering is relative, so for someone who was born into royalty, won the genetic lottery, and never really had to want for anything, having a special occasion ruined by a delayed delivery of their favourite champagne will cause them to suffer - as will the loss of their inherited wealth either through personal financial ineptitude or some other personal failing, or just unavoidable circumstance like war or a natural disaster - leading them to need to live more frugally, but still in brick and mortar habitation with running water and electricity like most of us do, hopefully.
On the flipside, someone living a typically middle class lifestyle, or even in fact, just in a country with generally reliable working indoor sanitation, will find it a massive inconvenience if their toilet breaks temporarily, whereas someone who grew up where open defecation is still the norm and open sewers abound would presumably be grateful not to have to shit into a hole or hovering on the shore of a literal river of shit, even if they had to walk outside their home to do so. My point is that this sliding scale goes all the way up and all the way down and someone who appears to live a life of luxury will not be free from suffering - in fact in many ways they will be more vulnerable to it as they will be so used to pinning their happiness on external things, and this is true even if they never actually lose these things and die happy, although it would be fair to say they would have lived a particularly lucky life, were this the case.
It seems that everyone I know does not enjoy life. My mother says she has never really enjoyed being alive but discounts suicide, my father doesn't ever discuss these things with me.
This to me is very sad. It's quite possible to enjoy life while accepting that struggle and suffering are an inevitable part of it. I would say that despite the inevitability of suffering, it is by no means a default or healthy state to never enjoy being alive, in fact most people would consider this to be a treatable psychological dysfunction which one should seek help for. There are many things in life to enjoy and that make life worth living, although for sure, they can be hard to find at times.
Is everyones life pretty much difficult?
Again - yes. But the fact that everyone's life is difficult and that we all need to find a way to accept this does not mean we should accept that struggle and suffering
are all there is, and all we can hope for. If you or anyone you know feels this way, they are depressed, and the reasons for this are in some sense immaterial - there are still ways to be less depressed.
Granted again, the reasons for someone's depression may appear more or less understandable. If I was kidnapped, had both arms amputated, and was incarcerated in a North Korean gulag with no apparent hope of rescue I would probably become very depressed and start to feel life was hopeless, and most people could understand why more than they would understand the tantrum of a silver-spooned aristocrat over a delayed champagne delivery. Although even then hopefully I would not allow this depression to manifest into such a nihilistic state of mind that I would steal bread from a starving child, for example - and most of us would like to think that were we born into the life of this hypothetical aristocrat, we would not throw tantrums and make other people's lives harder over such trivial things.
I guess what I am trying to illustrate here is the value of trying to find a way out of depression for as long as we feel in any way able, and finding a way to act as a sponge for the suffering of life for those who cannot - without using words like "duty" or implying any kind of moral imperative because I think that's an ethically tricky road to go down and not necessarily helpful for those who do feel truly hopeless. Anyway I hope you take something useful from this.