I think your point number 1 is one of the quickest ways TO feel lonely. I've found my personal happiness and satisfaction should absolutely not be fully dependent on having a girlfriend. That mentality often causes people to settle or remain in relationships when they shouldn't.

When you have habits that keep you happy and healthy, then often times things fall into place like getting an SO, but I hope I never "get" a girlfriend to make me stop feeling lonely. I should have daily habits that provide me with a fulfilling life, then I won't feel loneliness. I prefer entering relationships as a balanced, happy person.