Bella, I found 8 months really, really hard with both of mine - neither slept at all, at that age there is still lots of milk feeding to do but also lots of solid food being thrown around that needs cleaning, they were crawling so just wanted to be on the move, but of course you can't exactly just let them crawl round Tesco or Costa so all the 'put them in the pram and go out for some sanity' places were suddenly nigh on impossible as they just screamed to be moving. It was awful. Things honestly got so, so much better at around a year once they were starting to walk and talk. Hang in there.
I know I sound like a mn cliche here, but one thing that really helped me was doing some baby signing. Find a class, or just learn a few signs online or from Mr tumble. Food, drink and more are great signs to start with as the baby tends to be sitting still in a high chair. If you are consistent they pick it up pretty quickly. I found it reduced frustration for both of us and I felt I was learning things too.
Also, the outside support you have makes a massive difference. I, like you, have none and it is hard, hard work. I am several years down the line now and look at parents who have always had a granny on hand - to babysit every now and then or help out when kids are sick off school, or even just keep them company for the afternoon and make them a cup of tea - and I just think they don't know they're alive. It's not just the actual 'time off' it's the mental stress of knowing you don't have that safety net if something happens. Never underestimate how hard it is without support or beat yourself up for finding it hard.
Finally, don't be scared by people telling stories of the terrible twos. I remember thinking 'gosh this is hard and apparently it will get even harder -
argh'. I absolutely loved having toddlers. Yes, they are hard work, but they are also hilarious, fascinating and they Do Stuff. Good luck.