[Ennui.]

I'm not sure if there's a word for it but I've heard it being called being afraid of conflict. You're worried about how the other person will react or don't like the possibility of it turning into something bigger, so you avoid it. At least that's how I'm understanding what you are saying. It's not pathetic and it's definitely a normal thing. A lot of people worry about what is going to happen with their friendship/relationship/work status/etc when there are disagreements, even civil ones. I know that for me personally I got an email from my boss that I disagree with and have conflict with but instead of defending myself politely I'm just ignoring the email and hoping it'll go away So it's not just you.
I think for part of it it's practicing tone. If you're disagreeing over text, email, Facebook, etc it's a little harder to master this because it's really hard to tell tone when you can't hear someone's tone of voice or see their body language. It's a little easier in person, although still difficult. I've heard a lot of people use "I statements" because that makes the other person less defensive about what you have to say. An example I heard in my DBT class has to do with having asked someone to take out the trash at night, and they never do. "I noticed the trash has not been taken out. I feel like I am not being listened to when this happens." This is instead of "you statements" like "You made me feel like I'm not being listened to because you didn't take out the trash when I asked." You statements put the entire blame on the other person and makes them more defensive.
My DBT class also told us about DEAR MAN, GIVE FAST. It's an acronym I'll explain below.

• Describe the problem non-judgmentally while just stating the facts of the problem.
• Express how you feel about what's going on using the "I statements" I described above.
• Assert your needs clearly and firmly. "I need the trash to be taken out at night."
• Reinforce your point and also state what the other person gets out of the interaction.
• Mmindful of the other person and your posture, tone of voice, facial expressions, etc. Try to remain calm.
• Appear confident
• Negotiate and be flexible
• Gentle - Be gentle and kind when you talk. Use "and" statements instead of "but" statements. Instead of saying "I see what you are saying, but this is my point," you can say "I see what you are saying, AND this is my point."
• Interested - act interested in the conversation
• Validate the other person's feelings.
• Easy manner - look calm and relaxed.
• Fair - Be fair to the other person and check the facts of the situation.
• No Apologies - do not apologize for your thoughts or how you feel.
• Stick your values and do not compromise your values for the other person.
• Truthful - Be truthful about what happened and stick to the facts without inserting opinions.

This is supposed to help you communicate more effectively with another person.

I hope that helps a little!