Please, please do NOT leave your dog unattended with only a few visits from friends. There are lots and lots of options that will keep your dog happy and safe.
Many kennels these days are lovely and the one we use welcomes visitors, and also allows you to take your dog for a day trip(free) first before you go away so both you and the dog can get used to it. Many kennels or even dog hotels will feed your preferred food, send you pics and emails and can do things like training, grooming etc during the stay.
Dog boarders would accommodate your dog in their own house - again, your dog can take their own bed, food, toys, brushes etc and the boarder will be experienced. Both kennels and dog boarders are licensed by the local authority, so you can see their license and read their inspection reports.
Pet sitters (either friends or professional) are also a good idea but you should agree before hand how long they can go out and leave the dog, check they are competent to walk the dog (and ensure dog is not let off lead), and agree a written protocol for authorising vet treatment etc. For this reason, it may be better not to use a teenager, unless they are very sensible or have good parental backup.
It's possible to develop the doggy equivalent of a "babysitting circle" with fellow dog owners. Try people who walk at your park, at your training classes, via your vets, or via the rescue/breeders where you got your dog. Many breeders are also very happy to see their dogs for a weekend. We have greyhound sleepovers with various houndy friends and it works brilliantly if the humans need to go away for a night or have a special occasion such as a wedding.
I know exactly what you mean - being away without ours left us feeling utterly bereft, but honestly they will be fine if you choose carefully.