First of all, she did the right thing to break up with you because you certainly take the break up way too personally. Having feelings for someone is nothing you can control. Why I tell you that she did the right thing? Let's say she didn't break up with you (despite having no feelings for you), she would certainly have a miserably marriage with you and divorce you at some point in the future, where you may have had children. At that point in the future, you would be much more affected by this - and would react at least the same way as you do now: wanting to kill yourself. Just imagine that for a moment. YOU would have left alone your children on this Earth with her mother, and the children always remembering you as someone who has commited suicide and you would have left your ex-wife guilty as shit and would mentally and psychologically destroy her and thus also your imaginary children. I know it's hard to experience a break up after 4.5 years of thinking she is the right one, but you can go through all of this. Please don't suicide. You will not only destroy your life, but the lives of your family and especially of your ex-girlfriend.

I wanted my children to have her eyes.

Please. Stop even thinking about children that are not there! She used the emergency brake which you should be tahnkful for instead of wanting to kill yourself. See it like this. You have a relationship worth of 4.5 years now. In the next months you will think of all the mistakes you may have done and eventually accept that despite (everyone does mistakes) you have done mistakes, it's just okay that she doesn't have any feelings for you anymore. Let's put it like this:

Let's say you are in a relation-ship with Sophia, but after 4.5 years you finally realize that it's not the right thing to be in a relation-ship with her anymore for what reason ever it may be, and the most creditable reason is having no feelings for her. Now imagine that Sophia wants to kill herself because you broke up with her. How would you feel about that? You wouldn't want her to kill herself but also, you would say "I've I knew that she would react this way, I'd never even fall in love with her at the beginning". Am I right? I repeat, I can imagine how hard it is to be left alone and behind like that. It may be more of an embarressment than being hurt. But really, she's not worth ending your life. Talk with your family about it. See friends. Throw away anything that reminds you of her. Start a new life. Buy new clothes, re-decorate your rooms. Change something but do something man, just don't commit suicide.