Firstly, question about priority is stupid. There are no rulebooks of life for everything and in many cases only outcome matters, not a way t achieve it.
Secondly, no one can really make you happy. Happiness comes from appreciation (either genuine or selfbullshitting which is surprisingly effective, but many people underestimate their own brains) and biology (stuff we are conditioned to to create chems which improves our mood, for examples endorphins created during physical activity). If there were some other rules on this you wouldn't have depressed bilionaires or couples, and happy/carefree nigs in africa or lone people. In fact, when you take into consideration whole globe, EU and US should have no sad people at all.
You can appreciate anything, every small detail. It can be taste of some food, it can be sounds, it can be work done right, it can be just laying, listening to silence and resting, even someone's else happiness, or if you believe the theory of selfishness being behind everything, you can appreciate someone's else appreciation of your actions.
Your character can affect ease of appreciation of various stuff to some degree, but it isn't 100% full and solid.
Someone else can just give you additional material to appreciate, for example you cann't have sex or discussion including different views etc alone. There is even difference between you touching yourself and someone else touching you. For example have you ever wondered why it's easy to get tickled by someone else, but it's hard to tickle yourself?
So yeah, someone else can help you achieve happiness, but there's only so much they can do and final step, appreciation, will always be your job.
Also this anon
>>186056 has right idea about fleeing from responsibility, dropping your burden on someone else and it being unfair. I'll just add that sometimes people are really weak/stupid/whatever. It's just how life is and you can't do shit about it, not everyone is truly equal. You can be unable to get better or decide not to, but don't expect to be treated equally, become follower, not leader or even "partner". You can't eat a cake and have it. It can only be done by taking away someone's else cake. At least have enough decency to not do that.