I'm looking for a situation where:

• Girl falls in love with a guy who already has a partner (lover/fiancee/wife) and she doesn't try to chase after him
• She doesn't dwell too much on her feelings (NO nurturing a heartbreak, 'what-to-do-with-this-feeling' brouhaha, trying to find new love etc)
• The guy has to reciprocate the girl's feeling
• They maintain whatever relationship they had before they started to develop feelings for each other (friends, boss-subordinate, partner, etc)
• The guy does love his current partner (probably different kind of 'love', nevertheless she is important for him) and at some point chose her over the girl he loves
• Even if the guy breaks up with the current partner, it's not because he ditched her for other girl
• The guy's current partner has to have a respectable personality, and preferably has a 'good end' for herself.

Don't want:

• Draggy love triangle that involves a second male lead, if the love triangle only involves the girl, the guy, and the guy's partner it's okay
• Too much inner monologues that focus too much on characters' feelings
• Yuri, yaoi, shounen-ai, shoujo-ai, harem

Examples:
Tokyo Crazy Paradise
Beauty is The Beast
I Love Her
Secondary couple from Gokinjo Monogatari

Thank you ~

DONDAKEE!!

It's been a while since i read it but Oishii Kankei definitly fits what you're looking for

NG Life maybe. The male lead's lover is not someone from the present though, but I feel like it still fits most/all of your requirements.

Sakuranbo Syndrome

@cherry59: started reading it based on your recs, it's a good manga and perfectly what I'm looking for. Thanks!

@Restart: I've already read this one but yeah it kinda gives the vibe of what I'm looking for (chill, ambiguous relationship with occasional heartache)

@annebel: gonna try it, thanks!

Any more?

DONDAKEE!!

Fated to love you - I didn't finish it, but I think it does have a draggy love triangle you don't like. It's also been adapted into a drama.

Strobe Edge

Chinese Translator Accepting translation requests if the manga interests me!

I think your description fit with what Nanba Atsuko often made. Especially Ao Natsu

Second strobe edge

Koibana! - Koiseyo Hanabi definitely.