As Khloe Kardashian celebrates her 37th birthday, her ex-beau Tristan Thompson took to his Instagram to share a heartfelt greeting to the 'Keeping Up With The Kardashians' star, but fans aren't impressed with his actions.

On Sunday, Thompson shared a series of sweet photos of him, Kardashian, and daughter True, "Happy birthday @khloekardashian Thank you for being not just an amazing partner, mommy and best friend but also being the kindest, caring and most loving human being I've ever met." the NBA star wrote.

"Your love and spirit is contagious to all who've met you. Thank you for always being there for me and putting our family first. I love you so much. Have an amazing day." he concluded with heart emojis.(check out the post below)

His greeting came after the news of their breakup circulated. At the time of this writing, Kardashian seems to be ignoring the basketball champ as she did not publicly respond nor share the birthday post on her Instagram stories.

Fans react

Following his greeting, fans quickly took to the comment section to share their disappointment with the NBA star saying that he doesn't deserve the 'Good American' CEO.

"I wish Khloe can realise her worth, and stop allowing you to toy with her", one wrote.

"Ummm you are everybody's man apparently sir leave her alone and let her enjoy her birthday." another one wrote.

"When you love someone, you are faithful. You wouldn't continue to go out of your way to bring pain to her , especially when she is the most amazing mommy out there to your daughter." one commented.

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Tristan Thompson and Khloe Kardashian breakup

Over the past week, news broke out about Thompson and Kardashian's split. According to a source who spoke to People, the ex-couple are "not together" anymore.

They added that reality TV star has been "very frustrated" with their on-and-off relationship and has been working so hard to trust the "Boston Celtics" player.

Even though things didn't work out, the two have been doing their best to be on "good terms" for them to be good co-parents to their 3-year-old daughter.

Following the news of their breakup, Thompson attended a party in Bel Air where he was seen entering a room with three women and went out looking "dishevelled" after 30 minutes.

According to The Daily Mail UK, an eyewitness revealed that they saw the NBA star grabbing the butt of one woman at the party several times.

The party happened just a day after Thompson and the "KUWTK" star spent a day with their daughter.

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