Hi nicky.
I hope you're better although drained I expect!!
After a low point, I had to take a week to sort out DS's sleep. After a week of trying, he'd be better.
I had to get anal about naps and making sure he wasn't overstimulated. I banned excitement after 4pm and wouldn't let him stay awake more than 45 - 90 mins. He was very excitable!!
It's easier to tackle the morning nap first - so after 40 mins of being awake (inc feed and dressing) I'd watch DS for tiredness and out him to sleep usually by rocking to some dance music as he liked a beat for some mad reason. I'd have him face a boring wall usually in a dim room. He'd nap on me.
Next nap - same again, watch for tired signs and pop in the sling and go for a walk. Sometimes he'd cry but I'd give him the dummy, keep walking and pat his bum to send him to sleep. Sometimes he'd go for two hours, not always though!
Naps later in the day were always harder - I'd need to spend more time winding down and he'd usually stay awake a little longer. Wind down would be carrying him around usually.
We had a super short bedtime routine - and no playing (I was anal). I'd let him watch us from the sling or bouncy chair then change, feed, bed. He would start off the night swaddled in his Moses basket then we co-slept.
It sounds simple - it wasn't. My ILs thought I was mad but if he didn't nap he didn't sleep at night. One evening we had visitors and showed DS off. He didn't sleep til 3am!!!!! Never again.
I became expert at reading his tired signs - he'd get a glazed look, no eye contact, would look away then he'd get super excited, flapping arms etc. So I knew he needed a nap.
Now at 10 months I'm still hot on his day sleep but I have to be otherwise he won't settle.
Perhaps you and DH can try sorting out naps - use any means and stick at it for 20 mins. If it fails, swap or take a break. Your DS will pick up on your tension making it harder to relax him.
It will get better and some days it won't work. But keep trying and it'll pay off.