Can't complete HC

I’ve been playing this game for a year or two. And created about 30 chars trying to complete this game on hardcore, but i always die in random levels.
i tried every single class. Should i feel bad ? Every time i fail(die), i stop playing for some weeks, then i return to try again.

I bought the crucible DLC, is it better to leveling than campaign?

If you’re playing on normal and you keep dying, it probably means you don’t get enough life in your builds.
Consider putting 1-2 points in your mastery with every level up and putting all stat points into Physique.

Not at all. You are just terrible with aRPGs and this one in particular. Live with it and just play the game if it’s fun for you. Never forget that you surely got abilities and talents others don’t. And this activity simply isn’t one of them, happens.
Enjoy the journey and never give up.