These situations are always hard, but it sounds like you're taking it very rational and mature. Sometimes tough decisions need to be taken in order to move on and both of you have a happier life.
It's good to know that drawing the cartoon helped you express your feelings, and even though it's super sad (especially the last two frames) I'm really glad you had the time to share how you feel.
And you might feel like you're alone, but remember that you still have friends (online and offline) and we're here to help anytime :)
It's getting a little long but I wish you both the best and a bright whatever future brings