A heartbroken man recovering from a brain tumor feels "lost and hopeless" after discovering that his girlfriend might have cheated on him.

"I had surgery several months ago to remove a tumor from my brain. The tumor caused damage on its own, but the surgery caused more severe damage that’s irreversible and un-treatable, and could eventually spread and lead to me needing to have part of my brain removed. It’s affected my memory, my ability to read and write, and further exacerbated my ADHD to crippling levels," the man shared on Reddit.

The man explained he used to be a writer which, to him, defined who he was.

"Now I struggle tremendously to write. It’s like pulling teeth and everything needs an insane amount of revision to even be coherent, much less good. Writing this post will take a lot out of me. I still haven’t been able to come to terms with having lost this ability," he recalled via his Reddit post.

His girlfriend has been his "saving grace" throughout his ordeal, supporting him both "emotionally and financially." That is, until he found out she might have been cheating on him, too.

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"I just found out that they’re back in contact with someone they weren’t supposed to be in contact with, someone who was plenty happy to try to break us up before. They’ve been hiding it and don’t know that I know. I'll probably never say anything and just let it happen," he shared, noting he doesn't "blame" her for talking to someone else.

"I might look elsewhere if my girlfriend [were] literally brain-dead and having so many seizures she lost large chunks of her day and couldn’t remember anything. But it really, really hurts. I lost my mind, my ability to write, and now I think I’ve lost my love. I’ve lost everything, and all I can do is accept it," he added.

The man concluded his post by admitting he feels "lost and hopeless."

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Reddit users in the comments section offered the man comforting words.

"I just want to say, this was very well written. There must be hope that you can write again. It has only been a few months. Your body and mind have been through so much trauma! I hope you are able to get into therapy and on an ADHD medication regimen that works as best as possible. Take your time with everything. Give yourself time for everything," one person wrote.

"You're doing great! Don't be discouraged. Your girlfriend may be showing her true colors at the most unfortunate of times, but from one writer to another... you're not alone and I for one am powerfully cheering you on," another reader shared.

"First of all, your partner sucks. Don’t excuse their actions by putting yourself down. In a relationship, love should be unconditional and your partner should be by your side supporting you during what is most likely the hardest time of your life ... [but] your life is not over. There have been many people in a situation like yours who have been able to regain back what they lost through physiotherapy and practice. You will get there too, please don’t give up," someone else commented.

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