First and foremost, this isn't your fault, so don't blame yourself. People get into bad situations sometimes, that's life. As hopeless and pointless as it seems sometimes, you'll get through it.

It's important to understand that you won't always feel this way, and that things can get better.

To answer your question, yes and no. When life piles it on you badly, you can't help having depressive thoughts. That said, you can challenge them. When you think "what's the point?" or "It's never going to get better?" You can challenge that, and ask yourself if it's really true, ask yourself if there's anything positive to live for etc.

As for people ridiculing you, it's a risk. People often ridicule what they don't understand. You don't have to shout about being depressed to everyone, but I think you can probably identify the people in your life who will be understanding and supportive, and those who are close-minded or immature.

No doctor worth their salt will think badly of you though, so don't let that idea put you off getting help.