بسم الله الرحمن الرحیم
In regards to your question that asked concerning:
Difference between na mehram friendship and na mehram love
relationship?
This sentence of you is true that you mentioned:
I told him that for me na mehram love relationship and na mehram
friendship is equally haram no matter you love or just friends.
Actually haram is haram. But the negative amount or degree of that can be more effective in it. The following two verses can help you to some extent. Hence pay heed to them carefully.
وَمَن لَّمْ يَسْتَطِعْ مِنكُمْ طَوْلًا أَن يَنكِحَ الْمُحْصَنَاتِ
الْمُؤْمِنَاتِ فَمِن مَّا مَلَكَتْ أَيْمَانُكُم مِّن فَتَيَاتِكُمُ
الْمُؤْمِنَاتِ ۚ وَاللَّـهُ أَعْلَمُ بِإِيمَانِكُم ۚ بَعْضُكُم مِّن
بَعْضٍ ۚ فَانكِحُوهُنَّ بِإِذْنِ أَهْلِهِنَّ وَآتُوهُنَّ أُجُورَهُنَّ
بِالْمَعْرُوفِ مُحْصَنَاتٍ غَيْرَ مُسَافِحَاتٍ وَلَا مُتَّخِذَاتِ
أَخْدَانٍ ۚ فَإِذَا أُحْصِنَّ فَإِنْ أَتَيْنَ بِفَاحِشَةٍ
فَعَلَيْهِنَّ نِصْفُ مَا عَلَى الْمُحْصَنَاتِ مِنَ الْعَذَابِ ۚ
ذَٰلِكَ لِمَنْ خَشِيَ الْعَنَتَ مِنكُمْ ۚ وَأَن تَصْبِرُوا خَيْرٌ
لَّكُمْ ۗ وَاللَّـهُ غَفُورٌ رَّحِيمٌ ﴿٢٥﴾
And whoever among you cannot [find] the means to marry free, believing
women, then [he may marry] from those whom your right hands possess of
believing slave girls. And Allah is most knowing about your faith. You
[believers] are of one another. So marry them with the permission of
their people and give them their due compensation according to what is
acceptable. [They should be] chaste, neither [of] those who commit
unlawful intercourse randomly nor those who take [secret] lovers. But
once they are sheltered in marriage, if they should commit adultery,
then for them is half the punishment for free [unmarried] women. This
[allowance] is for him among you who fears sin, but to be patient is
better for you. And Allah is Forgiving and Merciful. (25)
http://tanzil.net/#trans/en.sahih/4:25
And
الْيَوْمَ أُحِلَّ لَكُمُ الطَّيِّبَاتُ ۖ وَطَعَامُ الَّذِينَ أُوتُوا
الْكِتَابَ حِلٌّ لَّكُمْ وَطَعَامُكُمْ حِلٌّ لَّهُمْ ۖ
وَالْمُحْصَنَاتُ مِنَ الْمُؤْمِنَاتِ وَالْمُحْصَنَاتُ مِنَ الَّذِينَ
أُوتُوا الْكِتَابَ مِن قَبْلِكُمْ إِذَا آتَيْتُمُوهُنَّ أُجُورَهُنَّ
مُحْصِنِينَ غَيْرَ مُسَافِحِينَ وَلَا مُتَّخِذِي أَخْدَانٍ ۗ وَمَن
يَكْفُرْ بِالْإِيمَانِ فَقَدْ حَبِطَ عَمَلُهُ وَهُوَ فِي الْآخِرَةِ
(مِنَ الْخَاسِرِينَ ﴿٥
This day [all] good foods have been made lawful, and the food of those
who were given the Scripture is lawful for you and your food is lawful
for them. And [lawful in marriage are] chaste women from among the
believers and chaste women from among those who were given the
Scripture before you, when you have given them their due compensation,
desiring chastity, not unlawful sexual intercourse or taking [secret]
lovers. And whoever denies the faith - his work has become worthless,
and he, in the Hereafter, will be among the losers. (5)
http://tanzil.net/#trans/en.sahih/5:5
Meanwhile, I suggest you to pay heed to the two sites below as well as some matters which can be related to your inquiry too:
In regards to your last inquiry that asked "Please tell me the punishment or sin is equal or not?"
The response would be related to the amount of the relationship. In truth, whereas commonly the relationship in a loving relationship is stronger/closer, then haram acts (such as touching, speaking…) would be more in that relationship. Of course the significant point is that totally it depends upon the degree of haram practice(s) in the relationship.
And the last significant related point is concerning the relationship to non-mahram. Actually we considered the matter as a haram relationship to non-mahram. But in common relationship (I mean talking in the emergency positions, without the intention or the probability of the sin or lust or so forth, e.g. asking a necessary question or other similar items) cannot be counted as a haram act. (If there is not the hesitate of sin…)
May Allah guide us
Reference: