My boys are lovely 
There was a phase about 15-17 when I found my eldest very difficult to like, but it passed, and it didn't change my love for him. He got a job waiting tables when he was 17. It taught him so much about how to be a nice person at a time when he was rebelling against us. He never got into any trouble, no drugs or anything like that. He was just a sarcastic, arrogant little toerag for a while. His friends were all nice and I never had any hesitation having them at our house (except one generally sweet guy who was only welcome if he was sober!)
My current 15yo is a head taller than me and hasn't yet got the hang of adult personal hygiene without reminders. Like his older dbs, he drapes himself all over me for hugs and kisses wherever he wants them, which isn't always when I want to give them, but hey-ho.
They all choose to introduce their girlfriends to me, help around the house, and can cook basic stuff. My eldest is really developing his cooking skills at uni, and frequently consults me or shows off his creations.
I've always respected their privacy, especially once they reached their teens. But, equally, I've always made sure to go into their rooms when they're in them, or sit with them on the sofa or at the table, and just check in with them. Every day.
They're smelly and noisy and hairy. Yet when I hug them I can still feel the soft little boys.
My boys and my girls are different, but I don't know whether it's a difference because of being different sexes, or because of being different people.
(Though TBH the smelliness, even after rediscovering shower gel and shampoo, is purely down to being male!)