Tenacious, he sounds just like my daughter was at that age. Just wanted to be held all the time, 2 short naps in the day, waking at night, etc. My family live overseas, DH's family lived 200 miles away, we were new to the area so I didn't know anybody and DH work 70-80 hours a week. It's all still fresh in my memory, 10 years later, and one of the big reasons I didn't have any more children. I feel for you!
I put my daughter in nursery 2 half days a week so I could have a break, but almost always spent that time cleaning house, ironing, etc - things that seemed impossible with a baby that wanted to be held constantly.
At around 6 months, we did controlled crying. I absolutely hated doing it so my husband did it and after 3 nights, the crying stopped. She did still wake in the night tho and ended up in our bed when that happened. I was just too exhausted to fight it. We also started her out on baby rice at 4 months. When she was about a year old, she started having 2-hour naps - absolute bliss!
She's 10 now and I know I'm biased, but she's a lovely, well-adjusted girl. I never have to chase her to bed - she just gets ready and that's it. She has no food allergies or intolerances, will eat almost anything and is very loving, caring, thoughtful and polite.
The only thing I wish I did differently when she was a baby was not worry constantly if I was doing the right or wrong thing and not compare my parenting style to others. It turned out all right in the end! Well, so far anyway - we have the teenage years to get through! ;)
The only thing I can say is it WILL get better, but at this stage I know that feels an eternity away. X