A sincere thank you.

There seems to be an inconsistency in your capitalization here, (this is more grammar than poetics), but at times you capitalize on new sentences, other times you don't, and you don't seem to capitalize your "i"s, which might be a stylistic choice, but if not should probably be done.

There is also a great variation in your line length, which makes the poem flow weirdly. The second line especially is quite run on simply as a sentence on it's own, and could definitely be split into 2 lines. Perhaps also add a comma to make it feel less "breathless" to the mind. You could also make the 5 lines before the last take on a more "poetic" form, to give a better flow to the poem, and to add more of an emphasis to that which you're saying.

I feel like the period between the last two sentences is strange, as the first sentence of the two doesn't feel to be a complete thought, and the two sentences feel as if they should be linked. I also don't entirely understand what you're trying to convey with "showing me what a real woman is", are you implying that because she's shown you the way some woman can be amazing, you'll never be able to accept another ever again? That meaning I found to be hazy.

What I liked: You adopted a fairly direct narrative style and stuck with it which was refreshing. I love imagery (and I use it a lot myself) but sometimes poems can get bogged down, a problem which yours avoids. I also liked the repetition that you include (I just want to... X2) and then switching it up to "I just need to....). The repetition adds structure to the poem and adds emphasis the the "NEED".

What maybe could use some work: I was immediately frustrated by the inconsistent use of punctuation and capitalization throughout the poem. You could cut out the first period in the 8th line and in the 12th line. The ellipsis were also unnecessary and didn't add anything to the work. If you want to keep the punctuation then please, please capitalize after your periods. The last line introduces some tension to the piece which, though appreciated, is a little confusing and verges on outright antithetical. Additionally, the 7th line (in your eyes you've done nothing for me to be thankful) introduces the tension that you're looking for with you're final line (I doubt I could ever forgive you) and it does it half way through the poem which robs the finale of it's force. I would keep one or the other but not both. I suggest you cut out the last line, move the 7th line to the end, and then replace it with another stanza. Finally, and this is just nitpicky, I would change the 2nd line such that it refers only to what you didn't know you wanted rather than make a claim about all humans. I think that will make the poem a little more personal and avoid the risk of the audience reading the poem then thinking "Well know I know that I want what he has even if I don't 'have it in front of' me" which renders the second line just plain false. Again that's kinda nitpicky but that was my experience upon reading the poem.

I definitely noticed the formatting and grammar, but other people commented about that already. In the first couple lines, there is some repetition that I'm not sure if I like. I do like the details in the third line that describes that "something." I also like how you capitalized "need" to stress the importance of that need. usually, people don't need to thank people but by stressing the need you definitely showed a different perspective than most people think about when saying thank you. There are some formatting issues that other people have mentioned, but overall, I think that it's a pretty good piece of work because of the repetition and details.