Asalamualaikum wrt wb,
All praise be to Allah, whose veil is Light.
True success is following the Prophet, may peace and the blessings of Allah be upon him. We have to remove our hatred and ill-feelings towards the knowledge. This hatred or revulsion to the knowledge is from the Shaitan, who wishes to lead us astray.
Signs of this disease of the heart, is that when knowledge is mentioned, the person tries to change the subject, or attacks the speaker, or has ill-feelings towards him or her.
The Prophet, may peace and the blessings of Allah be upon him said, "One of you will not believe until his or her desires are in accordance with what I came with." ie. the Sunnah.
I ask Allah for all my brothers and sisters, that they are able to remove their revulsion and repulsion to the Sunnah, and the knowledge, and the scholars, and that He change it to love.
As for your question, it seems that you should set a date, or a deadline for this proposal. If it does not come through by this date, then you should move on. Whatever date you set, whether it is 1 month, or 3 months, or 6 months, stick to it.
If things do not work out by that date, then it will become permissable for other suitors to propose to you. But since you are currently considering someone, it is not permissable for a brother to propose over the proposal of his brother, and you may be missing out on someone better.
And Allah knows best.