What in my birth chart shows why I am always single?

I am a guy in my late 20s.

Your chart is a little bit similar to mine, and I can tell you that with the majority of planets in your 12th house, your true self is “hidden”
Other people can see the disconnect easier than you can and it makes them uneasy. They will often be able to see any anxiety or awkwardness. It’s not fair, I know. The upside is that it’s all in Leo, another thing we share in common. Believe me, you have a lot of creativity and talent just waiting to burst through the surface and shine. I would focus on maybe taking a drawing class or film editing or basket weaving or whatever the heck is interesting to you that is creative and all that talent you have will come out and grab the attention of a like minded soul. Good luck and trust yourself.

you are right.

Agree about your hidden talents!

You could also have some hidden enemies too (Mars = Men + Jupiter =expansive) so you may have a lot of dating competition behind the scenes. Another possibility: it may mean hidden aggression (either by you or others). Pluto energy is also magnifying what you have in the 12th and/or breaking it down. In contrast, Alec Baldwin has Mars aspecting Venus but it's in Aquarius (can mean "loud") so his aggression is right out there for all to see (about his loved ones).

Out of curiosity, have older women shown interest? There is quite a bit of Capricorn energy that may contribute to that.

Some astrologers say that the star or planet that is in proximity plays a part and I noticed Chiron (wounded) in the 11th (friends/hopes & dreams) next to your Venus. If you use that "healing" energy you may find your true love. Perhaps a friend (11th house) who is a healer (mind/body/spirit practitioner) would introduce you.

I noticed that you have 12 degrees in Capricorn btw. That is a very fortunate star.

Venus opposes Saturn, and in addition to the oppositional energy, Saturn does not get along well with Venus because Venus is in the sign of Saturn's detriment, Leo.
Under the best of conditions, with Saturn in the mix, things take time. And when I look at it from a whole sign house system, you have Saturn in the 7th sign/house of relationship.
Regardless, of the house system you use, Venus Saturn says to me that romance comes later, when one is more matured.

in case this helps take stock, do share feedbacks how true-insightful :


jup-moon-mars-venus leo 12th, detached/indifferent attitude towards life;
aptitude for medicine, martial arts, advisory-trainer aptitudes;
high self-pride, commanding attitude; seeking foreign lands;

jup-sat opp, misjudgments-missed opportunities;
moon-sat opp, emotional stress, economic, worrisome;
mars-sat opp, stress and struggle, tech-mech-entrepreneurial aptitudes;
venus-sat opp, artistic aptitudes, craving for affection but not manifesting,
mutual health issues in marriage-relationship;

sat lord 7th negating to the 8th, negating relationship/quality thereof;

mer lord 11th negating to 10th, gains from career,
but negating friendships-relationship;
sun-mer gemini analytical, but confused at decision making;

lords 1/7 sun-sat over gemini-acq trine semi-friendly lords,
quick attractions and repulsions in a relationship;

rahu NNode 5th cap, foreign relationships; tech edu, delayed children, etc

ketu separative SNode cancer 11th, hyper-sensitive;
detachment from income-gains-friendships-relationship;


ketu now 1.5yr transit sat-acq 6th, accident prone, job separation;


rahu the giver now 1.5yr transit venus-leo 12th,
inclined to foreign lands and foreign relationship, to hope for;


jup now transit own sag trine venus, supportive;
promoting art-advisory roles etc; trine aries 9th supportive of luck;


sat however transit own cap 5th, seeking change, but stuck;
negating employment opportunities;
while may be good for public admin, event management aptitudes;
natal sat acq 6th, reformist, innovative, technical aptitudes,
retro towards cap 5th, negating employment prospects again;

sat lord 7th for relationship too, to note/care, transit ketu now;


aries-mars inimical for leo asc, stress-delays in luck-edu-father-travels;
jup trine own sag 4th protective of domestic comforts-property-mother;
trine aries 9th protective of luck-edu-father-travels;


prayers to Christ, offer red flowers at the alter at home mon evenings;
observe fast sat evenings taking milk-fruits;
prayers to saint of faith, offer yellow flowers sun mornings at the alter at home;


do promptly ack, share feedbacks,


kshantaram

12th house planets. Venus opposite Saturn, Venus square Pluto, Pluto square Moon. A challenging chart for personal relationships. 12th house planets' energies are difficult to show, or they can be more indirect. Compassionate, able to receive help from others. Pisceans and 12th house people I know, they attract a lot of goodwill. They tend to be more evolved. Happiness through spiritual pursuits.

Get yourself out there, you can try online dating, speed saying, join clubs, go to bars, coffee jobs, have a social circle, approach females.

Dress up well, groom well, relax, have good posture.

Just go for it.