In this case, you are talking with your boyfriend so it can be quite informal. Therefore we would use "I'm sorry" as oppose to "I want to apologise" or any other forms of apologies. Then you could say "I upset you" if he was sad, or "I made you mad/angry" if he was angry.
この場合、ボーイフレンドと話しているわけなので、かなりインフォーマルな可能性があります。ですから、"I want to apologise" などではなく "I'm sorry" が使えます。
その後、もし相手を悲しませたなら "I upset you"、怒らせたなら "I made you mad/angry" と言えます。
If you got into a fight with your boyfriend and you wanted to apologize for making him upset or angry you could say any of the following: "Sorry I upset you", "I did not mean to upset you and I am very sorry" or "I’m sorry for making you mad". All three of these are apologies and allow you to express that you are sorry for your actions whilst you were having a fight.
ボーイフレンドとけんかをして怒らせてしまったことを謝りたいなら、次のように言えます。
"Sorry I upset you"（怒らせてごめん）
"I did not mean to upset you and I am very sorry"（怒らせるつもりはなかったです、本当にごめんなさい）
"I’m sorry for making you mad"（怒らせてごめん）
これらは全て謝罪をする言い方です。あなたがけんか中にしてしまったことについて謝ることができます。
It is always best to offer an apology when you have upset someone. You can start by saying "I'm sorry!" or "I apologize!". Then you can make a follow-up statement apologizing for what you did. "I am sorry I made you mad, angry or upset." You can use whichever emotion your boyfriend is feeling. You can also add, "Please forgive me."
人を怒らせたときには謝るのが一番ですね。
"I'm sorry!" または "I apologize!"で始めることができます。それに続いて、自分のしてしまったことを謝ります。
"I am sorry I made you mad/angry/upset."（怒らせてごめんね）
あなたのボーフレンドの感情に合わせて使い分けることができます。
また、"Please forgive me."（許してください）と加えることもできます。
To have your feelings hurt or to be feeling sad about something means you are 'upset' if you have a fight you sometimes get 'angry or mad ' with the other person as well
By saying sorry you are apologising and saying you wish it didn't happen
The two sentences you see provided above are terrific ways to express to your listener that you are sorry for upsetting them. In the second sentence you will see the word hurt. Although this word can be used in different ways in this sentence it means to upset or make someone feel sad. This word would make a great addition to your vocabulary and can be used in both formal and informal settings.
If you want to apologize to your boyfriend for making him upset, you can say:
"I'm sorry for upsetting you."
"I'm sorry that I made you mad."
"I didn't mean to make you angry."
彼氏に「怒らせてごめん」と謝りたいなら、次のように言えます。
"I'm sorry for upsetting you."（怒らせてごめんなさい）
"I'm sorry that I made you mad."（怒らせてごめんなさい）
"I didn't mean to make you angry."（怒らせるつもりはなかった）
So sorry for arguing like that - you know it's only because I love you!
Please forgive my behaviour - it's just that you drive me crazy sometimes!
I know I make you mad sometimes - I don't mean to. Please understand, it's only because I have such deep feelings for you!
You got into a fight with your boyfriend and now want to apologise for making him upset or angry. Above are a few suggestions which may fit this situation. There are follow up comments with each example apology as it seems a little short if you just apologise without giving some kind of excuse or reason for your behaviour. You do not actually apologise in the third example - but you give such a good explanation about how you feel, that it is equivalent to an apology in its function.
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