Questions: Girl's Behavior

Suppose there are two guys at your work place and both are of your age group , given both are almost similar in terms of looks/height etc..

But they behave differently as in:

A.) Guy A greets you/smiles initially in the day , takes every opportunity to make a conversation with you, be next to you , makes regular eye contact whenever necessary, talks other things as well apart from work.

B.) Guy B rarely tries to greet you /pass a smile by himself. If you greet him he simply replies back. Never tries to talk to you or have a conversation with you. Mostly tries to ignore you/ you presence and doesn't make any eye contact unless very necessary for work.

Few years ago I went on several dates with a girl who admitted to her friends (I was told later) that I was being used for food, rides, and gifts and she said that she'll dump me after the holiday season is over. I got to know about it after the breakup where she made up a reason and broke up.

Few years later (yesterday) I see this girl, she was voluptuous before, but now she's overweight and really lost her looks. I wanted to know if purely to satisfy my ego or vengeance can I make fun of her in public because since then I've worked on myself gotten a job, built a physique, etc.

Do women set the standard for dating.

Men seem to just want every girl. Like if a girl is a b**** the reason she doesn’t change and act nice is because men still flock to her. Men need to make women accountable for their actions. For example if a man is rude all women will be turned off by him.