You should ask both lawyers for a complete copy of your file and consult with another personal injury lawyer in your area immediately. You should not spend time worrying about why they dropped your case. You may only have a short amount of time left before your case must be filed. Another lawyer should be able to advise you on the merits of your case and give you some guidance on what to do next.
Acting quickly is of paramount importance. You may have rights that will go unprotected unless you take quick action.
I agree with the above comments in the "answer to you" post.
Also, you should request in writing of both your former counsel to provide the file materials on your case to you.
Meanwhile, make sure to continue to care for yourself.
Any new lawyer trying to help you sort out your situation would need quite a bit more information before he or she could do so.
Your question refers to a "case," but it's not clear whether your original lawyer, or the one he referred the case to, actually filed a lawsuit or not.
If you original lawyer worked on the case for "a year and a half," but didn't file suit, that suggests that you may be very close to -- or perhaps beyond -- the two-years statute of limitations that Texas applies in personal injury cases. That's why I agree with the lawyers who've previously commented here: Your situation may be very urgent, and you may be at risk of losing rights permanently if suit hasn't been filed. Even if suit has been filed, you may want to reconsider -- with the help of counsel you trust -- whether all of the proper and/or necessary defendants have been sued.
You say that your original lawyer "referred" the case to someone else. It's not clear from your question whether your original lawyer got your consent to do that, either in the original contingent fee agreement you signed with him or at a later time. That may become very important. It's also important to learn whether your original lawyer purported to transfer or assign his contractual rights to the new lawyer. (You didn't mention signing a new contract, but if you did, that would be important too.)
It's also important to know whether your original lawyer formally resigned from the representation, whether he's withdrawn as your counsel of record (if suit has been filed), and whether he's released his contingent fee interest in your case.
You may want to take a look at a self-help guide I've written here on Avvo, which I've linked below. In addition to your other problems, a serious question may arise as to whether your original lawyer, or the lawyer he "referred" the case to, might later claim to still be entitled to either a percentage of your recovery -- even if that's achieved with the help of an altogether new lawyer -- or, possibly, some other sort of reimbursement for his/their time and expenses. If your original lawyer indeed abandoned you and your case, you may be able to show that you have "good cause" for formally discharging him and a defense against having to pay him for his time and (possibly) even his expenses. But you may want to document that all now.
Of one thing, I'm quite certain: You ought not try to sort through this by yourself. You may want to make one last effort to talk through your concerns with the "referral" lawyer. But it seems likely that you need to consult someone entirely new to the situation to get a completely independent opinion, as part of which he or she will doubtless as the same sorts of questions I've posed here.
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