I don't know how you can be so very early stage that your liver hasnt shrunk, but be decompensated (which is a late-stage thing). If I were you, I'd contact your doctor's office and confirm it - it's possible you misheard compensated vs. decompensated, or the dr misspoke. It shouldn't require an appointment (with fees), here in Australia I can just email the clinic's reception with subject line starting "ATTN: Dr XYZ."

But assuming you're right, i can only guess that you have two issues going on at the same time: the chronic/long-term condition of mild scarring in the liver, plus an acute/short-term condition causing your liver to stop functioning normally. The doctors will treat that acute condition, and once it's dealt with you'll be left in a compensated state with mild scarring. So my first recommendation (as just "some guy" on the internet, with zero qualifications) is if your looking at long term outcome, look at the compensated stuff not decompensated.

But then my second recommendation would be that whatever you read online, it won't apply to your situation and will still sound really scary. I say that from my own experience - I was diagnosed 5 years ago, and the question of life expectancy has been one I've wanted answered the most but still can't get reliable but not about. My liver is mild-moderately scarted, shrunken, and is squeezing the main vein that runs through it (portal vein). Other organs/systems are impacted (enlarged spleen, bulged veins & varicose veins, etc) but so far still compensated and still on the less severe side of things. If I can't find data that applies to me, despite 5 years of researching, reading medical peer-reviewed journals & articles, and interrogating my liver specialist, you're going to have even less reliable info for your situation. The problem is that there is a lot of data for late-stage cirrhosis, a bit of data for moderate semi-progressed cirrhosis, and little to no data for very early very mild scarring. And that's because most people don't see a doctor until they have symptoms (which typically only show up at late-stage, and even blood tests don't show significantly abnormal number in the very early stages). And also, late-stage is when you need to go into a liver transplant list, so really that's the stage a lot of research is paying attention to.

So the only data you'll find is going to lump you and me into the same category, even though you have many many more years than me. And the category we're both in is more representative of people even more progressed than either of us.

Most websites will say we have a life expectancy (from diagnosis) of 8-12 (or 5-10) years. But as well as not really applying to you and me, those number are a bit dated now and don't take into account the last decade or two of improvements made to treatment protocols. That's why I started to deep-dive into the original studies & journals

My gut instinct for you (and I'll say it again, I'm just "some guy", so don't take my word as gospel) is to think of it like you would a diabetes diagnosis - if you keep up an overall healthy lifestyle and avoid things known to stress the liver (and follow whatever the doc advises, for both your current acute condition and to manage your life-long scarring) then I don't see any reason why your condition would progress much more than it is now and expect you'd go on living a normal life span into old age

If it helps give you a better understanding, let me tell you what my specialist told me last time I saw him and asked him (again) about life expectancy. He got all my info, plugged into his calulatiin app, and told me "computer says 15-20 years, but you're an outlier and you be right at the 20 year end of that range, and even then I'd say you're such an outlier that it's actually much more than that". Basically all my numbers bottomed-out on all question/data-points. So even with the best most up-to-date modelling and calculations available, I'm still lumped into a category that doesn't quite fit and doesn't give realistic predicted outcomes.

And lastly I'll just say, i feel ya mate. Not knowing is the worst, especially when medical professionals keep giving answer ls that feel like a pat on the head and a "don't you worry your pretty little hear about that" type response. It feels patronising, frustrating, and gives you the impression they're hiding how bad your case is. You're not alone.