Male lead is still in love with female lead

You can check out: ML Still Loves FL After She Hurts Him (If Not Even More)

I highly recommend The Romance of Tiger and Rose from the list, it fits your description the most!

 The Bishop:

Any drama where the ml and fl start dating and then fl breaks up with him but ml is still in love with her.

• High Society 
• Search: WWW
• Love in the Moonlight
• Moon Lovers: Scarlet Heart Ryeo

Dramas where the leads were not *officially* dating before the FL ended things with the ML, but they had gone on a few dates and kissed:

• Extraordinary Attorney Woo
• I Need Romance 3

Dramas where the leads sleep together either on the day they meet or very early on in their relationship and the ML falls for the FL but the FL either runs away (out of embarrassment), rejects the idea of starting a relationship, or both:

• Search: WWW - The leads sleep together the night they meet. The FL regrets it afterwards and initially resists the ML's attempts to start a relationship. Later on, she agrees to date him but breaks up with him due to irreconcilable differences (the reason I also listed this drama in the first list above). 
• Forecasting Love and Weather
• My Secret Romance

Dramas where one lead tricked the other lead into dating them, where the leads agree to fake date, or where the leads get married before falling in love, in each case before the FL ended things between them - and the ML was still in love with the FL after that point:

• +1 The Romance of Tiger and Rose - The leads get married before falling in love. Then the ML falls for the FL (thinking that she fell for him first). Then the FL seemingly betrays the ML and sends him away. She does it for his own good, but he doesn't know that. 
• Because This Is My First Life - The leads agree to a marriage of convenience shortly after meeting one another, but both develop real feelings soon after. 
• The Blue Whisper: Part 1 - To achieve certain objectives, the FL convinces the ML to trust her and then convinces him and others that they are in love. The ML is innocent and naive enough to fall for it. The FL later develops real feelings for the ML and, to save him, has to convince him that she had always been using him and never loved him.
• Tempted - To win a bet, the ML pretends to have feelings for the FL and woos her into dating him. But then he develops real feelings for her and has to suffer the consequences when the FL learns the truth.
• Her Private Life - The ML offers to fake date the FL to protect her from rumours / angry fans of an idol (and what he mistakenly believes is her secret sexual orientation / relationship with a woman - because he's a good ally). The FL reluctantly accepts (not realizing his assumption). Both leads quickly develop real feelings for each other, and the ML wants to end their fake relationship so they can start a real one. The FL misunderstands his intention and ends their fake relationship first. 

• Begin Again
• Our Beloved Summer
• Dear.M