lastingly

always endlessly eternally permanently

evermore perpetually

durably enduringly everything considered for always for ever and ever for good for keeps for life forevermore immortally in perpetuity in perpetuum infinitely interminably now and forever on and on till Doomsday till blue in the face till death do us part till the cows come home till the end of time unchangingly world without end

briefly never temporarily

forever

enduringly for good for keeps