Who should organise the wedding feast (waleemah)?

The basic principle with regard to the wedding feast
(waleemah) is that it should be organized by the husband, because he is
the one who is enjoined to do that, as it was narrated by al-Bukhaari
(5155) and Muslim (1427) that the Prophet (blessings and peace of Allah be
upon him) said to ‘Abd al-Rahmaan ibn ‘Awf: “May Allah bless you. Give a
waleemah even if it is with just one sheep.” 

Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) said: It
(the waleemah) is prescribed for the husband, because the Prophet (blessings
and peace of Allah be upon him) said to ‘Abd al-Rahmaan ibn ‘Awf (may Allah
be pleased with him): “Give a waleemah,” and he did not tell his in-laws to
do that. And because the blessing is greater for the husband than for the
wife, because he is the one who sought the woman; it is very rare for the
woman to seek the man. End quote from al-Sharh al-Mumti’, 12/321. 

And he (may Allah have mercy on him) said: The questioner’s
stating that responding to an invitation to a wedding feast is obligatory
does not apply in all cases; rather that refers to the wedding feast that is
offered by the husband. Accepting an invitation to this feast is obligatory.
Similarly, if it is organised jointly between the husband and the woman’s
family, accepting the invitation to it is obligatory, because the husband is
the one who is enjoined to provide the wedding feast, because the Prophet
(blessings and peace of Allah be upon him) said to ‘Abd al-Rahmaan ibn ‘Awf:
“Give a wedding feast, even if it is with one sheep.” If the wedding feast
is provided by the wife’s family only, and the husband is going to offer
another feast when his wife comes to join him, it is not obligatory to
accept the invitation of the wife’s family; rather accepting it is Sunnah.

End quote from Fataawa Noor ‘ala al-Darb. 

From this we may note that it is permissible for the wedding
feast to be organised jointly between the husband and wife, or the wife’s
family may organise it. Similarly, the wedding expenses may be shared as
agreed between the two parties, and each of them may offer a wedding feast,
as is customary in some countries. If there is some dispute as to who is
obliged to provide the wedding feast, it is to be provided by the husband,
as stated above. But other wedding expenses, such as having a party in a
hotel and so on, should be done according to mutual agreement. 

And Allah knows best.