Honestly, it is extremely difficult to prevail on a claim that is based on a verbal promise and/or contract
In most cases, it's a he said/ she said situation, however with your ex-boyfriend dead, his family would simply deny that any of this occurred, and it would basically be impossible for you to prove otherwise with you being the only witness to the promises that were made.
So, while you could make a claim on the estate based on these verbal promises, it is highly unlikely to succeed.
(It would be another story if you had something in writing, an email, or voicemails that stated this, but with just your word to go on, I'm afraid that you'd be facing a very hard uphill battle in proving your claim).
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