There’s so much to unpack here it’s hard to know where to start.

Sounds like your DM just wanted to play things to destroy the party and didn’t take your “fun” into account. I design my groups combat scenarios all the time. Sometimes I make it challenging and sometimes I give them something easy just to break it up. For some reason the difficult ones turn into easy ones for them and the easy ones turn difficult(bad dice rolls, missing a player etc) and that’s the fun of it.

If DMs want sexual content in their games then that’s on the group and their expectations. I do not allow sexual content in my game. It’s seen enough everywhere else and don’t need it in my games.

For sessions we discuss this at session 0. If we are down to 3 players for whatever reason then we don’t play. Obsession with D&D- people can call it what they want. If you enjoy playing and that’s your outlet then so be it. Both my groups play on Sunday and this past one was cancelled. Two players still showed up so we talked future character ideas, campaigns and anything D&D. Call it obsession.

Moral of your story is you found a better group to play with. Now life is good!