Do you want to know his real name or what? Jan Andrzej.

marcin in s2 was ideal on purpose. he was charismatic, tactful. he had the same ideas and way of thinking as aniela. they even color coded it to us in the last episode of s2 where they both wore blue clothes to drive the idea home that they are on the same page with many things therefore perfect for each other.

the script tries to make us believe that this is how it should be on purpose, that marcin is the better choice for her. she will face no sad consequences if she chooses him. and it's not like aniela is blind or dumb, she sees it and understands it. her mother's letters are what pushes her to make that choice, or rather sacrifice.

yeah but that's not how love works. aniela loves only one person and that person is maciej. and she loves him for who he is despite their different backgrounds and complicated situations. even her mom sees it, the person who arguably was the most adamant that aniela must marry a nobleman. but she herself knows that love is not like that and she chooses to let that love live and doesn't pressure her daughter anymore (we even see her happy for aniela in the finale of s3)