Can't handle being told they're wrong or ignorant about something.

Bragging about things not even in your control, like your parents' wealth.

The more you talk about how good you are in bed and how many women you've [slept with] the less I believe you.

All those people who post on Facebook those quotes that are like: ‘don’t worry about those who talk behind your back, they’re behind you for a reason’ Or they tag themselves into any and EVERY place including the docs/hospital/somewhere personal. Then when someone asks if they’re ok they reply with: ‘don’t ask hun xoxox’ Urgh so basically. People who live their lives through very active social media’s I suppose I’m trying to say.

People who feel the need to judge everyone in a negative light and who only want to see the worst in others so they can feel better about themselves. It just shows how unhappy they truly are.

I used to be very insecure so I'll go from my own experience. Lying about something to seem cool. It's very obviously a signal of insecurity because they don't like who they are now.

One-upping people constantly in conversations.

Women that guard their men like a soldier. I was leaving an abusive relationship my friend offered me a place to stay. The hitch was if she wasn't there and just her husband was I had to leave. I got a hotel room not dealing with that.

Being unnecessarily mean spirited to people

This is a self roast but I think I degrade myself just to hear others deny it, is that insecure?

being unable to sit in silence with others without talking, even if there’s nothing to talk about -making small gestures and then constantly seeking validation and reassurance that you are appreciated, even if there’s no reason to think you aren’t appreciated -constantly asking if someone is mad at you, even when they have told you several times that they are not mad at you -trying overly hard to be funny/likeable/smart around people who already know you well just to seek attention and validation

Bf:"Alright I'm going to work babe" Gf:" you better not be f***ing with b***hes at work"

Insulting random people's physical appearance.

Automatically assuming negative intent. eg: You friend didn't pick your call? "F her, she's trying to avoid me. I don't care about her anyway."

When you tell someone something positive or nice that happened to you, for example, that you purchased a new TV and that you start to notice that the other person always tries to poke holes in your cloud of happiness by saying you instead should have waited, the TV is too big, it consumes to much power, that brand is s***ty and so on. But they do this with everything you share with them that is somewhat positive to your life.

Constantly wedging "humble bragging" into conversations.

People whose self-esteem is so low that they can't stand the sight of people with high self-esteem, so they will try to break down anyone they perceive as more successful than them. When a group of this type of people comes together, a major crab bucket mentality arises and they will target people perceived as highly competent or successful for bullying, gossip, false rumors, and other things that should have been wiped out after elementary school.

When people have and insist on constantly checking on their SO via some tracking app on their phone. It's one thing to have it and use it in case of emergency, but using it while out with your friends to make sure he's actually at work is creepy and super insecure.

A constant need for affirmation.

Incapable of self reflection

Joint Facebook profiles

I’ve found that a lot of people on Twitter that feel the need to post about how great of a person they are and they have nothing but good intentions are usually the most toxic people I’ve seen

People who constantly tell stories to make themselves seem real tough or badass. Yeah, dad, that's really awesome that you kicked some guy's ass when you were in the marines 40 years ago.

Socially aware individuals understand that the other people have a life to run and might need a day or seven for them only. Insecure people are going to have a fit and from the first lapse of communication, they expect that they have been abandoned for some really abstract reason, regardless if it has any merit or not.

“I only get along with guys. Other girls hate me.”

They argue against your grammar, semantics, or micro-details, rather than the point you were obviously trying to make. "You showed up to work an hour late!" "No I didn't, I was an hour and four minutes late, don't you know the difference between 8:00 and 9:04!?" "OH S**T YOU SURE PUT ME IN MY PLACE, JOSH!"

Trying to dominate conversations (not to be confused with just being a charismatic person).

Oftentimes, people don’t know the difference between “telling it like it is” and just being flat-out mean. People who tell it like it only give their opinion when it is warranted because they would want someone to tell them the truth instead of dancing around it. however, some can cross this line and just be straight-up rude, while using this same reasoning. those who “tell it like it is” are secure, those who are unnecessarily mean are insecure. not exactly a direct answer to your question, but I’ve always thought this and wanted to share.

Lifestyle creep. Constant fishing for compliments when around people (eg, "I'm so chunky" as a direct way to get someone to tell you that you look great).