since even Mother Theresa didn't really believe in her religion, isn't that proof Islam is more believable?

Why no it isn't. The two things aren't logically connected at all.

Meaning, what exactly?

Mother Theresa was devout in her faith, but that doesn't mean she always felt great because of it. Considering that Christianity is a hard life to live, she certainly experienced, in her words, "dark nights of the soul". It is a testament to her faith and will that she didn't stray from her faith.

So to answer your headline question: no.

Edit: "It's pretty much known now, by searching even the google, that Mother Theresa most likely died not really believing. "

The two most important words in that sentence are "most likely", for it is your admission you don't know what you are talking about.

You'd better proof your unreliable source before making a statement like that.

And you said Islam people can feel Allah? Have you been voted all your people for that statement?

And how do you know that Catholic didn't feel Jesus?

Does Islam allow you to throw lies?

You'd better know when to stop writing!

You know what, as it's Christmas, and many miracles can happen, I'll pray to Jesus to open your heart, so that you can believe.

Having a doubt, now and then, does NOT mean Mother Theresa never really believed her religion in the first place. Let's be real.

For the sake of argument, let's PRETEND Mother Theresa really didn't believe her religion. . . . that in and of itself does not validate ANY other religion, period. Again, let's be real.

Mother Theresa remained a devout Catholic even when she endured "the dark night of the soul"

What has this to say of Islam?

We live by faith, not feelings. To say she couldn't 'feel' God but remained committed to the cause she believed He entrusted to her, speaks volumes. Many other saints have experienced prolonged periods of time when God seemed to withdraw from them.

Islam is known to produce some outstanding scholars and thinkers.

Who are you Really?

Islam is just another religion the world does not need.

Nope

Islam believers believe in God so....

islam is less believable as the kporan was plagiarised from other scriptures