Wanting a partner and not finding one
The canon does not treat the wish for a companion as a failure of practice. It calls good friendship all of the path, and its picture of a good partnership is two people matched in faith, ethics, generosity, and wisdom, which is a useful thing to look for. Its list of what to look for in a friend, from confiding in you to standing by you in trouble, is worth carrying into the search for a partner. Both can be true: the wish is reasonable, and the ache that runs the day can still be looked at. Nothing here tells you to stop looking.
What the suttas say
“Sir, good friends, companions, and associates are half the spiritual life.” Not so, Ānanda! Not so, Ānanda! Good friends, companions, and associates are the whole of the spiritual life. A mendicant with good friends, companions, and associates can expect to develop and cultivate the noble eightfold path.
Ānanda says half; the Buddha says all of it.
Where this stops: Never used to make someone without such friends feel that their practice is lacking.
SN 45.2:1.4–2.3 · Half the Spiritual Life
“upaḍḍhamidaṁ, bhante, brahmacariyaṁ, yadidaṁ—kalyāṇamittatā kalyāṇasahāyatā kalyāṇasampavaṅkatā”ti. Mā hevaṁ, ānanda, mā hevaṁ, ānanda. Sakalamevidaṁ, ānanda, brahmacariyaṁ, yadidaṁ—kalyāṇamittatā kalyāṇasahāyatā kalyāṇasampavaṅkatā. Kalyāṇamittassetaṁ, ānanda, bhikkhuno pāṭikaṅkhaṁ kalyāṇasahāyassa kalyāṇasampavaṅkassa—ariyaṁ aṭṭhaṅgikaṁ maggaṁ bhāvessati, ariyaṁ aṭṭhaṅgikaṁ maggaṁ bahulīkarissati.
Householders, if wife and husband want to see each other in both this life and the next, they should be equals in faith, ethics, generosity, and wisdom.
Nakula's parents — the Buddha's picture of a good partnership.
Where this stops: A picture of a partnership both people want; not a standard to measure a partner who broke faith against, and not a reason to stay.
AN 4.55:3.1 · Equality (1st)
Ākaṅkheyyuñce, gahapatayo, ubho jānipatayo diṭṭhe ceva dhamme aññamaññaṁ passituṁ abhisamparāyañca aññamaññaṁ passituṁ ubhova assu samasaddhā samasīlā samacāgā samapaññā, te diṭṭhe ceva dhamme aññamaññaṁ passanti abhisamparāyañca aññamaññaṁ passantīti.
Mendicants, you should associate with a friend who has seven factors. What seven? They give what is hard to give. They do what is hard to do. They endure what is hard to endure. They reveal their secrets to you. They keep your secrets. They don’t abandon you in times of trouble. They don’t look down on you in times of loss. You should associate with a friend who has these seven factors. A friend gives what is hard to give, and does what’s hard to do. They put up with your harsh words, and with things hard to endure. They tell you their secrets, and keep your secrets for you. They don’t abandon you in times of trouble, or look down on you in times of loss.
What to look for and what to be in a friend.
AN 7.36:1.1–3.4 · A Friend (1st)
Sattahi, bhikkhave, aṅgehi samannāgato mitto sevitabbo. Katamehi sattahi? Duddadaṁ dadāti, dukkaraṁ karoti, dukkhamaṁ khamati, guyhamassa āvi karoti, guyhamassa pariguhati, āpadāsu na jahati, khīṇena nātimaññati. Imehi kho, bhikkhave, sattahi aṅgehi samannāgato mitto sevitabboti. Duddadaṁ dadāti mitto, dukkarañcāpi kubbati; Athopissa duruttāni, khamati dukkhamāni ca. Guyhañca tassa akkhāti, guyhassa parigūhati; Āpadāsu na jahāti, khīṇena nātimaññati.
These six directions should be recognized: parents as the east, tutors as the south, partner and children as the west, friends and colleagues as the north, bondservants and workers as beneath, and ascetics and brahmins as above.
The canon's own map of a householder's relationships, the six directions, from parents in the east to ascetics and brahmins above.
Where this stops: Only the list of the six directions; how each one is looked after, parents included, follows it from DN 31:28.
DN 31:27.2–27.3 · Advice to Sigālaka
Cha imā, gahapatiputta, disā veditabbā. Puratthimā disā mātāpitaro veditabbā, dakkhiṇā disā ācariyā veditabbā, pacchimā disā puttadārā veditabbā, uttarā disā mittāmaccā veditabbā, heṭṭhimā disā dāsakammakarā veditabbā, uparimā disā samaṇabrāhmaṇā veditabbā.
“Householder’s son, you should recognize these four good-hearted friends: the helper, the friend in good times and bad, the counselor, and the one who’s sympathetic. You can recognize a good-hearted friend who’s a helper on four grounds. They guard you when you’re negligent. They guard your property when you’re negligent. They keep you safe in times of danger. When something needs doing, they provide you with twice the money you need. You can recognize a good-hearted friend who’s a helper on these four grounds. You can recognize a good-hearted friend who’s the same in good times and bad on four grounds. They tell you secrets. They keep your secrets. They don’t abandon you in times of trouble. They’d even give their life for your welfare. You can recognize a good-hearted friend who’s the same in good times and bad on these four grounds. You can recognize a good-hearted friend who’s a counselor on four grounds. They keep you from doing bad. They support you in doing good. They teach you what you do not know. They explain the path to heaven. You can recognize a good-hearted friend who’s a counselor on these four grounds. You can recognize a good-hearted friend who’s sympathetic on four grounds. They don’t delight in your misfortune. They delight in your good fortune. They keep others from criticizing you. They encourage praise of you. You can recognize a good-hearted friend who’s sympathetic on these four grounds.”
Friendship in concrete terms — one who looks out for you when you are off guard, one whose loyalty holds whatever your fortunes and who keeps your confidences, one who turns you from wrongdoing, and one who is glad when things go well for you.
Where this stops: The line that such a friend would even die for you is the outer edge of the ideal, not a test a friendship has to pass.
DN 31:21.1–25.3 · Advice to Sigālaka
“Cattārome, gahapatiputta, mittā suhadā veditabbā. Upakāro mitto suhado veditabbo, samānasukhadukkho mitto suhado veditabbo, atthakkhāyī mitto suhado veditabbo, anukampako mitto suhado veditabbo. Catūhi kho, gahapatiputta, ṭhānehi upakāro mitto suhado veditabbo. Pamattaṁ rakkhati, pamattassa sāpateyyaṁ rakkhati, bhītassa saraṇaṁ hoti, uppannesu kiccakaraṇīyesu taddiguṇaṁ bhogaṁ anuppadeti. Imehi kho, gahapatiputta, catūhi ṭhānehi upakāro mitto suhado veditabbo. Catūhi kho, gahapatiputta, ṭhānehi samānasukhadukkho mitto suhado veditabbo. Guyhamassa ācikkhati, guyhamassa parigūhati, āpadāsu na vijahati, jīvitaṁpissa atthāya pariccattaṁ hoti. Imehi kho, gahapatiputta, catūhi ṭhānehi samānasukhadukkho mitto suhado veditabbo. Catūhi kho, gahapatiputta, ṭhānehi atthakkhāyī mitto suhado veditabbo. Pāpā nivāreti, kalyāṇe niveseti, assutaṁ sāveti, saggassa maggaṁ ācikkhati. Imehi kho, gahapatiputta, catūhi ṭhānehi atthakkhāyī mitto suhado veditabbo. Catūhi kho, gahapatiputta, ṭhānehi anukampako mitto suhado veditabbo. Abhavenassa na nandati, bhavenassa nandati, avaṇṇaṁ bhaṇamānaṁ nivāreti, vaṇṇaṁ bhaṇamānaṁ pasaṁsati. Imehi kho, gahapatiputta, catūhi ṭhānehi anukampako mitto suhado veditabbo”ti.