Miscellaneous challenges, relationship friction, ego-related conflict

The character being passed over for a job due to their age or lack of experience
Being denied an apprenticeship based on looks, attire, a lack of pedigree, a disability, etc.
The character offering ideas in a meeting and being ignored
The character asking out their dream date who laughs it off, thinking it's a joke
Parents discouraging the character's dream because they think it'll go nowhere
A spouse not supporting the character's desire to run their own business
Family members viewing the character's passion (writing, art, breeding dogs, etc.) as a silly hobby
Being told that a career, membership, or opportunity is out of reach for the character
Volunteering to take on a leadership role and being blown off
Participating in a conversation and being patronized or dismissed

Losing face in front of others
Having to swallow pride and try again (because the ends justify the means)
Having to listen to "do this, not that" speeches by those who think they know better
Feeling let down by loved ones but being unable to show it (or the family drama will get worse)
Trying to increase credibility by taking up "serious" interests they're not passionate about
Having to suck up to the people in charge
Getting into frequent arguments with snide or dismissive family and friends
Having to lie (about their age, experience, talents, wealth) to be taken seriously 
The character going to extra efforts to prove their capability
Having to work harder and longer than others
Having to find a proxy to share their ideas so people consider them
Dealing with condescension from employers
Being put in charge of jobs that are below the character's ability level
Financial investments to improve appearances (buying a new wardrobe, taking a course, etc.) 
Having to suck up to the people in charge
Not being given the same opportunities as friends, family members, or co-workers