Toddler won’t leave me alone

My little boy has been ill pretty much all of December with multiple colds and norovirus and it’s turned him from a Velcro baby to a superglue baby. I basically cant leave his sight for even a minute. He’s on day one of another cold and he just wants to have 100% of my attention all the time. It’s getting impossible to do anything. I’ve not been able to feed him a proper meal all day because as soon as I put him in his highchair he starts crying hysterically and stretching out his arms for me to take him. Nothing can distract him. I tried putting him on my lap while I eat and maybe feeding him as well but as soon as I sat down he started getting frustrated and pointing at the door to the living room. I’ve managed to follow him around with some food while he plays but he’s only taken a few bites here and there. He only wants boob. It happened again at dinner time but I was so exhausted and just wanted to eat my meal without being screamed at so I asked his dad to take him to play upstairs and he immediately started crying hysterically and calling out ‘mama mama mama’ it was heartbreaking to listen to so I wolfed down my dinner in like 5 minutes and went to get him. He immediately wanted boob and got himself so exhausted from getting so upset that he fell asleep in 10 minutes (bedtime has been an hour+ long struggle recently). We co sleep as it’s the only way we can all get some sleep and I can’t even leave the room once he falls asleep for more than 5 minutes. It’s like he senses I’m not there anymore and wakes up crying. I feel so bad for him bless him he just wants to be close to me but because it’s been going on for like a month I’m getting really exhausted and burned out. He was a bit ill on Christmas Day and we were hosting my partner’s family. As soon as his sister (he’s not seen her for a good few months so I think he’s forgotten who she is) stepped through the door he had a huge meltdown and I had to take him upstairs to calm down. He only wanted me and cried every time we went downstairs to join everyone so I ended up spending most of Christmas Day by myself with him in his room. I didn’t get to eat my Christmas dinner until everyone left bc he was just so clingy it was stressing me out. He finally relaxed like 20 minutes before the guests had to leave so we only got to spend 20 minutes with everyone. Can someone please tell me this isn’t just us and it’s a phase that’ll pass. It’s getting so overwhelming and the pressure of being his only comfort person is really stressful. Like I want to do right by him and make sure he feels safe and secure but I’m only one person and I feel like I’m failing him. He’s always been a ‘Velcro baby’ but I thought it was getting better around September/October time and me and my partner were even talking about having my mum watch him while we go out for a few hours but since the start of December all that’s gone out the window. Sorry for the extremely long post but the whole situation has been really weighing on me and I think I just needed to let it out. I keep seeing these fairly happy, easy going toddlers out and about and can’t shake the feeling that I’ve done something wrong somewhere or that I’ve failed as a mum.