Any manga like Boku no Kareshi no Sukinahito?? http://www.mangago.me/read-manga/boku_no_ka...

Which aspect?

sorry, havent read that manga, but after reading the sinopsis I think these ones, fit:

http://www.mangago.me/read-manga/bokutachi_futari_ga_koisuru_riyuu/

http://www.mangago.me/read-manga/bokura_ga_koi_wo_ushinau_riyuu/

http://www.mangago.me/read-manga/brother_x_brother/

http://www.mangago.me/read-manga/tenjou_no_shita_ni_koi/

A younger brother in love with his older brother but trying to get over him

oh! then from my list the only one that doesnt fit is the first one and the last one, btw
heres another one:
http://www.mangago.me/read-manga/toshishita_no_ryuugi/
and here is the tag

http://www.mangago.me/tag/step+brothers/