What were Shakespeare's personal feelings about love?
First, as stated in an earlier answer, we do not know what Shakespeare's personal feelings were about love. We do not have any existing diaries or letters in which he explicitly stated his personal feelings. Instead, what we have are literary works, plays and poems. In his plays, various characters express a wide range of opinions about love, but we cannot assume that any of the characters voice Shakespeare's personal opinions. Similarly, in Shakespeare's poems, the narrators of individual poems express different ideas and sentiments, but we cannot simply assume that these narrators voice the personal feelings of the poet. Instead, they often seem to follow the conventions of the period and genres in which they were written.
In Sonnet 116, Shakespeare argues for a notion of love that is transcendent and spiritual. This is actually a quite common convention we also see in Petrarch's sonnets, in which the beloved is portrayed as an anagogical ideal, partaking in the characteristics of the divine (perfect, unchanging, unaffected by events in the sublunary sphere). The physical beauty of the beloved leads the lover's soul to contemplate the transcendent divine beauty of which all physical beauty partakes in this particular conception of love. One should note, though, that this concept does not appear in all of Shakespeare's sonnets and thus is likely simply to reflect one of the standard conventions of late medieval and Renaissance poetic love rather than a personal opinion.
If you are studying Shakespeare in much detail you will find, if you haven't already, that when you attempt to ascertain anything "personal" about him, such as your question about his "personal feelings about love," there are a wide variety of opinions. Some, if not most, think of Shakespeare as a very talented and prolific individual. Others, however, because of the amount and variety of work that bears the name "Shakespeare," believe that there was no one person by that name but that various authors wrote using the same name. This and the lack of personal materials (personal writings, letters, etc.) make the determination of "his personal feelings" about anything impossible to ascertain. But that is another consideration.
In Sonnet 116 as in many other works, Shakespeare sees love as something transcendent—not something that might happen as a result of relationships and circumstances but the motivation for the relationships in the first place. Love is seen as an ideal, a virtue, a soul-task that is the result of mental and spiritual effort.