Can someone please tell me...

The reason their dad didn't contact them was because he was hunting the demon that killed Mary (the mom) and he felt it was too dangerous to get them involved that's what the job he was doing was. And in bloody mary the reason Dean started to be affected by her was because when he busted her mirror he released her spirit which pretty much increased her powers and the only way to put her to rest for good was to show her her own reflection. Anymore questions feel free to ask I like answering...oh and yes there are sex scenes and love in the show it's usually at least 1 in a season. I could give you each episode for each season if you'd like.

Season 1: Route 666
Season 2: Heart
Season 3: They didn't have any because it was mainly focused on trying to save Dean from hell but we do see Sam walking in on Dean in the act...very funny scene
Season 4: I know what you did last summer
Heaven and Hell
Also in Sex and Violence Sam has sex with a doctor I can't really remember if they showed it or just hinted at it...but still it's a good ep it really shows the divide between the brothers starting to grow and it's kinda sad.

If u watch the first season, u have left 4 seasons. Their dad can't contact with, because as he told to Sam, he hasn't finished his job and it's not time for it yet.

Ummm, to catch up to where it is now, you have three seasons left.

there dad dosent show up because he sold him self , and you have 7 seasons left (not counting books)